Any Love Interest that the hero meets is either wormfood or otherwise removed forever from his or her life by the end of the episode or arc. Named for the hunky Cartwright family, father and three sons, of Bonanza. This also happened in the case of any love interest of the males on Bonanzas competitor, The Big Valley (or maybe not just the males; after all, their mother was a widow when the show opened and their sister wasn't exactly lucky in love herself). If the two of them wind up getting married, it's even worse — chances are that he or she's not even going to make it through the ceremony or to the honeymoon.
If they're together at the end of an arc, be prepared for Sudden Sequel Death Syndrome in the next one. If the show has any amount of spy intrigue, there is at least a 50% chance that the new love interest is working for the other side and/or milking the relationship for intel; on intrigue-heavy shows such as 24 and Alias, this probability approaches 100%, and odds are good that the hero will be required to personally contribute to his or her sweetie's demise.
Puts the "Temporary" in Temporary Love Interest and serves as the "Yank" in Yank the Dog's Chain. Is a subtrope of Doom Magnet. Don't expect these widow(er)s to be particularly shook up at this untimely parting.
The reason for all this romance being cut short (besides an authorial inclination for their heroes to stay single and available) is the fact that many villains just can't resist tormenting the hero however they can, particularly by going after friends, family and loved ones (and even the Team Pet!) of the hero. It's little wonder that many Genre SavvyCelibate Heroes (who have likely been through this multiple times) have an "It's Not You, It's My Enemies" speech handy.
In TV series, this is often caused by the closely related trope Status Quo Is God. Fatal Attractor is a variation of this, except that the love interests in question usually survive, but prove to be woefully unsuitable for the hero in some way, if they don't turn out to be bad guys. Sometimes the two of these are combined, making for a character who really can't catch a break in the romantic department.
Compare Her Heart Will Go On, a variation where the love interest is killed off to show how strong and empowered a female protagonist is. Expect the Crusading Widower to have new potential love interests die to not distract them from their vengeance.
As a Death Trope, all Spoilers will be unmarked ahead. Beware.
It's more of a love/extremely close female friend dies mid-season to spurn the protagonist to greater heights, though almost exclusively in early UC and SEED. Mobile Suit Gundam has Lalah and Sayla for Amuro (though she doesn't die, due to problems with her VA, she was dropped rather than recast), Mobile Suit Zeta Gundam has Beltorchika for Amuro (vanished) and Four and Rosamia for Kamille (dead due to enormous, as opposed to giant, robot), Mobile Suit Gundam ZZ has Puru and Puru two, whom both die due to enormous robot. SEED has Flay for Kira, who dies, and Destiny has Stella for Shinn, once more due to enormous robot.
Terry Bogard in the anime version of Fatal Fury suffered from this. His first love interest, Lily McGwire, is killed by his nemesis Geese during the first TV special, while his second love interest, Sulia, ends up sacrificing herself to defeat her brother in the end of The Motion Picture. The video games averted this completely, by pairing Terry up with Blue Mary, who can take care of herself.
Tengen Toppa Gurren Lagann had the female version of this. Shortly after Yoko Littner and Kamina kiss, promising to begin their relationship after the upcoming battle... Kamina dies. In fact, both characters who kiss Yoko die shortly thereafter, though in fairness the second one (Kittan) went on a suicide mission knowing he'd die (Well there is a reason why she is nicknamed Doombitch...)
YOKO. You Only Kiss Once.
Likewise, Tsunade of Naruto also seems to suffer from this, ranging from her brother Nawaki, to her lover Dan, and finally to Jiraiya.
Black Jack seems to have this problem: all the women he loves either die, are already spoken for or, in one case, change their identity to male after a complete hysterectomy.
In Gatchaman Joe Asakura falls for one woman while on the racetrack who ends up being a Devil Star in disguise. He ends up killing her in a showdown as Joe the Condor being unaware of her identity, and is heartbroken when she doesn't show up later for a race they had planned. Just to rub it in further, it is revealed much later in the show that the woman was the fiancee of his priest childhood friend Alan.
Another woman accompanies him on an endurance race in one episode. She is shown to have a past with Joe and is a pretty assertive and confident lady, showing of her skills with her Cool Gun. However she is revealed to not only be from Galactor but also a cyborg and after learning of her treachery of trying to leave them, Galactor remotely self destructs her. Damn...
To a certain extent, Yuuichi from Kanon. Makoto "dies" at the conclusion of her arc, Mai and Sayuri are hospitalized for the remainder of the school year, Shiori has a terminal illness, Akiko gets hit by a out-of-control vehicle, and Ayu was Dead All Along (or better said, comatose all along). Granted, most of them are all miraculously healed in the final episode, but prior to that, Yuuichi has every symptom of the curse.
It's a good rule of thumb for a lot, if not all, of Key Visual Arts stories that the canonical girl who hooks up with the protagonist dies in some way, with Nagisa and Misuzu being prime examples.
As for Sara's love interests in Soukou No Strain, both get killed off in battle just as the relationship with Sara was getting serious.
Anyone who genuinely falls in love with Usagi of tends to die a lot. Mamoru/Endymion how many times now (though he always gets better). Prince Diamond/Dimande/Demand. And even Seiya is killed in the manga... Seems the only person who ever got spared for liking Usagi even the slightest bit was Umino who later moved on to Usagi's Best Friend in the first anime, and filler character Ali/Ail/Alan (but in his case, his sister/love interest commits a Heroic Sacrifice in order to save him, so he very nearly missed the mark there...).
And to further drive the point home, Mamoru himself also seems to have his share of dead love interests... Usagi/Serenity, Beryl, Fisheye...it just goes on... Lucky for Usagi and Mamoru that they aren't allowed by the story to stay dead, otherwise they'd have never lasted long enough to actually get together.
Ami/Sailor Mercury of the first anime has Urawa (Greg in the DiC English dub), who transfers to Juuban at the start of the episode and moves away by the end. He does get a second appearance for one episode later in the season, where he and Ami actually go on a date, but after the first season's Grand Finale, he's never mentioned again. In the finale, he was only seen as an illusion cast by the enemy to distract Ami and kill her.)
Lupin III: Given that the lack of continuity for this series/franchise means that none of the characters ever have a long term relationship, all five characters qualify. In this series, Love Interest means potential corpse. The only exception is Fujiko and Lupin's relationship. This curse is probably the reason Lupin will never get what he wants from her, though.
Only one of Madlax's love interests or would-be love interests is still alive at the end of the series. Apart from the survivor, only one of them was still alive at the end of the episode he/she was introduced in. Two of them died shortly after Madlax agreed to go on a date with them, but before the date could actually happen.
Masaru Katou from Gantz has really bad luck with women, as in all the girls that show interest in him tend to die. Might be why he prefers to cultivate his True Companions, particularly his bonds with his best friend.
Lelouch from Code Geass has three love interests (the main ones, at least; there are many more). Shirley dies and Kallen tries to kill him. In the end, though, it doesn't matter, because he can't be with any of them anyway. Also Nunally and Euphemia, who where both childhood crushes despite being his sisters. He caused the death of Euphemia and the apparent death of Nunally.
Shu Ouma from Guilty Crown, both of his love interests wounded up dead via Heroic Sacrifice. While he had three though the third was rather ambiguous and she survived at the end.
In fact during Blackest Night, one of his dead love interests taunts his current girlfriend by saying that she'll eventually end up like the rest of them.
Wolverine is "the best there is at what he does", and "what he does" is apparently "bury love interests" note actually, it's "make gratuitous guest appearances". The fact that he's functionally immortal means that he's accumulated a LOT of them. To be fair, one of them is still alive, but she is a crazy killer cyborg that wants to kill him.
Lampshaded in an old issue of Marvel Comics Presents, when Wolverine is tied up next to otherwise bland wannabe-Sabertooth villain Cyber:
Cyber: Did you know you recite the names of your dead girlfriends when you're unconscious? Wolverine: You should know, you killed one of 'em! Cyber: Ahhh, who hasn't?
One of them was killed by Spider-Man of all people. To be fair it wasn't his fault he thought she was Wolverine. She was trying to commit "suicide by cop"; she sneaks up behind him while he's still freaked out from fighting Wolvie. He spider-senses her, and punches without looking.
The secret it seems is to stay away from him for the rest of your life. One comic has Wolverine called by a woman he knew, and fell in love with, 50 years before. They go on a mission together, and several pages later she's lying dead in the wreckage of their plane.
Daredevil has had his share; four of his major love interests have died, and a fair number have gone insane.
The exception being Black Widow, though the same thing has happened to a few of her lovers. They probably just cancel each other out.
Semi-example: her love interests are fine, but Renee Montoya's partners/best friends tend to die tragically (see: Crispus Allen and Vic Sage). Harvey Bullock gets off easy with just leaving the police force in disgrace.
This trope applies itself in-universe to the main character, Alex, in Nightschool . When she was young, her best friend was driven to suicide and blamed Alex for it in her suicide note. The girl's mother, in a fit of grief-stricken rage, cursed Alex with something called a Neren Hex at her funeral, which functions as a literal Cartwright Curse. Anything she expresses even the slightest bit of affection for is instantly pulverized. Apparently, this is the reason behind her Jerkass Façade and homeschooling; she's terrified of getting close to people in case she slips up and something horrible happens to them.
Don't fall in love with John Wayne, or let him fall in love with you. You can be his friend, his surrogate daughter, or his friendly antagonist. You can even fall in love with his friends. But if you fall in love with The Duke himself, your chances of death are upped considerably. Your chances only improve if 1. You and the Duke are an estranged couple, looking for a reconciliation, 2. You're played by Maureen O'Hara, or 3. You marry another character, thus giving the Duke something else to angst about.
Duncan and Connor MacLeod of the Clan MacLeod of Highlander. Having people with swords hunting you doesn't help, neither does out living everyone you date!
Getting in bed with James Bond is, under Massachusetts state law, Assisted Suicide. Tracy, the one woman whom he married in On Her Majesty's Secret Service, didn't even make it to her honeymoon—and really, how cruel is that? Why else would anyone marry James Bond if not for the experience of the honeymoon? Even Dominique Paradis, the first girl in video game Nightfire gets kicked off a roof for her trouble. Generally speaking, it's best to be the second woman Bond hooks up with during the course of a mission. More often than not, the first woman he sleeps with is killed while the second survives. As an overall statistic, as of Skyfall, sleeping with Bond brings with it a 30.36% chance (17 out of 56) of dying before the end of the movie. Of course, this varies from Bond to Bond. Timothy Dalton managed to get a 100% survival rate (although in one of his two movies his friend Felix Leiter got married to a younger woman and guess what happened to her), while the current Bond, Daniel Craig, has reached a staggering 80% mortality rate, and it took him three movies to get below 100% dead (And the sole survivor of his lovers is a chick who appears in a vacation montage, who has a grand total of one scene and zero lines). Ladies, don't kiss him unless your will is in order.
It was implied Leiter's wife was an ex of Bond and there were still feelings. Which means even Dalton's survival rate is < 100%, if you count pre-movie nookie.
To a lesser extent, this happens to Martin Riggs (Mel Gibson) in the Lethal Weapon saga. His wife died in a car crash (but it turns out really she was murdered) before the first film, and his love interest in Lethal Weapon 2 slept with the fishes. Even Lorna Cole (Rene Russo) in Lethal Weapon 3 almost bought the farm, but ultimately subverted the curse.
The Death Wish movies were pretty notorious about this trope. Any woman Paul Kersey loved, be it his wife in the first movie, his daughter in the second one, and his girlfriends in the other three movies, were doomed to be killed off in vicious fashion in order to start up the Roaring Rampage of Revenge all over again. The only major woman he was involved with who didn't get killed off was his Love Interest in the second movie, who dumped him after finding out that he was a vigilante, and she was originally going to be brought Back for the Dead in the third or fourth movie.
A Gender Flip is the core of the plot of the '60s Shirley MacLaine comedy, What A Way To Go!! She plays a wealthy widow telling a psychiatrist her past 'luck' with her various husbands, each who die after gaining great financial success after marrying her. Averted at the end, after she marries her old formally-rich hometown suitor. It appears he's struck it rich as well, but she becomes relieved when it's shown he hasn't.
The extremely spiteful demon Asmodeus, and his habit of killing anyone who wanted to marry his victim. Since Asmodeus originates in the deuterocanonical Book of Tobit, this makes this trope Older Than Feudalism.
Richard Sharpe, from the Sharpe books gets a new girlfriend frequently. They always leave, either by running away with his money, dying, or otherwise being written out.
If Sinklar Fist, one of protagonists in Michael Gear's Forbidden Borders series, has anything in which he truly excels over his father and lifetime rival, Staffa Kar Terma, it's his bad luck with women. Whoever he gets romantically attached to, ends up dead, often for no discernible reasonat all. Sink is well aware of this curse and tries not to get too close to anyone by the end of the series, but, well, he's The Woobie...
A Song of Ice and Fire. Any man engaged/married to Margaery Tyrell ends up dead. She married Lord Renly Baratheon, who was assassinated and Joffrey Baratheon was assassinated on their wedding day. It's plausible that, after five books and three marriages, she's still a virgin. It's lampshaded when one character mentions that marrying Margaery is a death-sentence.
Given that her third husband is prophesied to die before his mother, he's likely to die soon too.
Nick Carter's spouse Ethel perished in Nick Carter Weekly #384, 7 May 1904, during a drawn-out battle with Dazaar.
Poor, poor Arsène Lupin can't keep a wife to save his (or her) life. Every woman he marries or otherwise hooks up with tends to not survive the book. (Or disappear between books.)
Averted in The Teeth of the Tiger. That one ends with Lupin happily married and retired, albeit under another name.
Donald Hamilton's character Matt Helm suffers from this, badly.
Travis McGee had this problem.
Burke suffers from this to an extent; the majority of his love interests are Put on a Bus, but Belle was shot to death by the cops while covering Burke's getaway at the end of Blue Belle and Crystal Beth was killed in an apparent homophobic attack on a gay rights rally (that turned out to be something else entirely). Belinda Roberts and Candy were killed by Burke himself (or Max acting on his behalf, in the latter case). They had it coming.
Harry Dresden. One ex he thought was both dead and evil (she came back, briefly), one woman who was turned halfway into a monster (and who he has to kill in a Human Sacrifice in Changes), and a woman who was revealed to have been brainwashed into falling for him. And when the poor guy makes a date for drinks and maybe some casual sex, he's the one to get killed. Guy can't catch a break.
Lampshaded in Redshirts, when one of the titular Red Shirts starts dating one of the head officers of the ship. Once she understands what's going on with the ship, she comes to the conclusion that her purpose is to make said officer depressed after she gets killed in some unlikely manner.
Bert Kling in Ed McBain's 87th Precinct series. The poor guy just can't catch a break. His girlfriends either end up dying, having too many issues to cope with a relationship, going off with another man or just getting fed up with him.
The Mortal Instruments: The trope doesn't apply to Clary, although when she meets Sebastian/ Jonathan for the first time she describes him as looking like a character from her manga who was this.
The House of Night seems to be heading in this direction. Out of Zoey's 4 lovers, two have died and one seems to be turning on her.
Felix Jaeger in Gotrek & Felix has two main settings in his relationships with women: either they leave him, or they die. He loses a girlfriend to a madman in a short story in "Trollslayer", his girlfriend in "Skavenslayer" leaves him for an old boyfriend, and Ulrika Straghof still exists, but as a vampire, so it's a little hard to rule on whether or not she counts as "alive".
Live Action TV
Bonanza is the Trope Namer. Ben Cartwright, the patriarch of the Cartwright family, has three sons from three different women. One of his wives died in childbirth, another died after falling from a horse, while the other one was killed in an Indian attack. Each Cartwright man has a string of girlfriends over 14 seasons, many of whom do not survive the experience. The worst man to flirt with, statistically, was the youngest, Little Joe Cartwright: over 14 seasons, he had 39 girlfriends, 25.6% of whom died. His girlfriend mortality rate became so legendary that other TV shows started to lampshade it. (For example, on Happy Days, Mrs. Cunningham refuses to watch any episode where Little Joe gets engaged, simply because "that girl is headed straight for Boot Hill!")
Buffy the Vampire Slayer: Xander Harris. Of his four major love interests, three are dead: Cordelia, Anya, and Renee, and all his other possible love interests turned out to be demons trying to kill him. Hopefully Dawn will have better luck.
In Smallville, Kyla and Alicia both died after being involved with Clark Kent.
In Kamen Rider Agito, any woman who doesn't want to get killed by an Unknown would better avoid Ryoo/Gills. The only one who survived was his FORMER girlfriend. Looks like she left him just in time!
While far too early to tell, this may be an affliction of a certain female crime fighter - terrorist in the newest V TV series.
Ruby survived a whole season after snaring him, but in the finale learned that explaining your plan to your Unwitting Pawn is a bad idea.
Played with in "Sex and Violence," when the boys are tracking a shape-shifting siren. When Sam sleeps with a hot doctor, the audience assumes she will turn out to be the siren and will be killed by the boys. She's not.
There may be an element of attempting to protect her from this effect in Sam's 'eh, why bother to say goodbye' reaction before they leave town. But mostly he honestly doesn't care much about her, which is a trauma-induced departure from his previous characterization; Dean hooks up, Sam dates. Only he doesn't, much, because it's not terribly compatible with their lifestyle and he's usually in mourning for someone. And when he does? Dean has actually killed two of Sam's more romantic partners himself. (Sorry, Kaylee - turns out the Winchesters CAN take the sky from you.)
He seemed to have gotten away from it for a little while. But then made up for it with four women in one episode.
Sam was already aware of this in season one, but Sarah Blake managed to avoid it...until it came back to bite herseven seasons later, all because Crowley felt like making a point. Ladies, avoid Sam Winchester at all costs.
In the episode, "Rock and a Hard Place", The Brothers Winchester become born again virgins as part of an investigation, when asked why he wanted to be a virgin again Sam replied:
Sam: Well, I guess because every woman I've...ever... had relations with, uh...it...hasn't ended well. '''
There are even two fan-names for the phenomenon. The "Peen of Death", or the "Dick of Doom". (It is generally accepted, however, that if you have to die in that crapsack universe, it's definitely not a bad way to go out. If that sounds dubious, go back and watch the season 2 episode "Heart" again.)
Dean doesn't fare much better. Most of his casual hookups make it out okay, but if he actually falls in love with you emotionally, watch yourself! Just ask Anna or Jo. Lisa had a huge chunk of her memory wiped, which is probably the only reason she's still breathing, effectively rendering her "dead" to Dean. And depending on your interpretation, note that Castiel has kicked the bucket a few times himself by now.
Castiel's now the deadliest to sleep with, simply because he's had sex once, and... she died. So he's running at 100%.
Misha Collins has said at a convention that (paraphrased) Charlie most likely will not die - because she's a lesbian, and is therefore not a sexual risk or attainable partner for the boys.
Any love interest (except for Lady Elizabeth) for the hunky father and sons, and hot daughter, of the knightly Grey family on Covington Cross.
Now consider that Daniel has come back from the dead multiple times, and Carter got snaked in season two.
Carter goes above and beyond the call of duty for this trope, as the men interested in her rarely die alone. Jonas (not Jonas Quinn), who lead one of the teams, murdered a teammate, set himself up as a god, then died with his Dragon when SG-1 incited a rebellion. Lantash, a Tok'Ra, took two hosts with him, the first when Carter had to Shoot the Dog, the second and Lantash himself in a Heroic Sacrifice. And Martouf, Lantash's first host who had been involved with the Tok'Ra who snaked Carter and transferred some of that affection to Carter, turned out to be a Manchurian Agent and was killed trying to assassinate the president in the abovementioned Shoot the Dog incident. Ambassador Joe Faxon let himself get captured to allow her to escape the Aschen, but then probably died with them if they dialed the black hole planet. Nerim was just one death in the genocide of the Tollan. And Fifth not only let RepliCarter loose on the galaxy, but was her first kill.
Even Alternate Universe versions of Carter are not immune: two that married O'Neill had him get killed defending their version of the SGC from Apophis' invasion.
"Girl in the Fireplace": Madame de Pompadour. Just found romance, offered her companionship, then he went through the fireplace only to find that he'd just missed her funeral. He should have paid more attention to the old fairy tales.
To be fair, Madame de Pompadour is a real historical figure and her death is probably a fixed point in time, so her death was inevitable. The fact that every time the doctor visited, several years had passed, set him up for this disappointment even if he didn't realise it.
"Forest of the Dead" puts a twist on it - thanks to time travel, he sees River die before their relationship has even started from his perspective. The pre-Library River is now a recurring character, meaning they both know a lot about the other's future that they can't divulge.
As a general rule of thumb, if the Doctor offers to let someone travel with him at any time before the very end of the episode, that person has an excellent chance of being dead before he or she gets a chance to set foot on the TARDIS (see Lynda, Astrid, Jenny, Reinette, etc.). This rule doesn't apply if he makes the same offer just before the credits roll.
In the Doctor Who Expanded Universe novels, he also has a dead male love interest. And one he was just a big jerk to and ran off on after being a bitch to him all the time. Plus one dead female love interest and one who gave him a taste of his own medicine and was just impossible. He also acquires a companion, Fitz, who has at the very least three dead, evil, or vanished love interests to everyone the Doctor has (plus a few male Not Love Interests — or are they?— who meet bad ends, too), and who enforces this trope upon himself by preferring traveling with the Doctor to staying with anyone. Seriously, fuck either of them and you'd better hope they just lose interest before they jinx you to death.
The only person Ace has ever had a relationship with who didn't meet a bad end was Sabolom Glitz, and even then their relationship was retconned in later by the producer after it had to be cut from the one episode in which they both appear.
Who says Sabolom Glitz didn't come to a bad end? He got stuck with Mel didn't he?
First with Kryten's fellow droid love interest Camille, who turned out to be a GELF that changes appearance depending on the viewer's true love (causing the rest of the crew to also fall for her), and her true form was an enormous green blob. She had to leave due to her husband Victor finally being reunited with her. Kryten lampshades the plot of the episode: "It's the old, old story. Droid meets droid, droid becomes chameleon, droid loses chameleon, chameleon becomes blob, droid gets blob back again, blob meets blob, blob runs away with blob and droid loses blob, chameleon and droid! How many times have we heard that story?"
This was used a second time with Rimmer's love interest Nirvana Crane, who gives up her position onboard the Holoship Enlightenment (and thus losing her life in the process) so that Rimmer can fulfill his dream of having a place on the ship. When Rimmer hears of this, he immediately resigns and returns to Red Dwarf, in order that she can continue living, despite the fact that the two will never see each other again. Rimmer says "We won't be apart, we just... won't be together. [Beat] I cannot believe I just said that!"
Notice the obvious solution: Switch 'em. Rimmer would get his dream job and Nirvana would get to... join... the... crew. Erm. Okay, Rimmer must definitely love her to be willing to spare her that fate, and the writers must have figured that we'd think that was an option, because the remaining crew of Red Dwarf spent their portion of the episode interviewing other dead crewmates to take his slot, and each declined. As one pointed out:
Candidate: No, I think I'm better off where I am, actually.
Cat (?): But you're dead!
Candidate: And meeting you three has helped me appreciate that a whole lot more.
Series X, in keeping with Rimmer's luck, introduces his perfect match - one of the greatest erroneous reasoners in the known Universe - and promptly chucks her out of an airlock.
Torchwood: Let's us pause to examine the fates of Toshiko Sato's love interests:
1. Mary turned out to be a Psycho Lesbian, wound up teleported into the sun.
4. John himself (during the period where there were two of him and the group split up) dies of radiation poisoning, complete with tearful deathbed scene.
Common in Inspector Morse, where Morse's love interests usually turn out to be either the next victim or the murderer. The spinoff Lewis carries on the trend.
Lampshaded in the first few seasons of Northern Exposure: everyone who ever got lucky with Maggie had eventually died in some freakish way (ate tainted potato salad, took a wrong turn into a missile range, fell asleep on a glacier and froze, was hit by a falling satellite shortly after learning he didn't have cancer).
Special Agent Leroy Jethro Gibbs of NCIS. His first wife was murdered, and the next three were divorced. Any woman he is seen to be in a relationship with is usually in one shot, and is gone by the end of the episode.
Even his exes aren't safe. Case in point: Jenny Shepard.
Samantha Ryan seems to be doing all right so far.
Actually fits Ziva of NCIS just as well or better - Langer, who she's implied to be in a relationship with, is shot by her coworker Lee, the man she falls in love with dies of radiation poisoning, and her serious boyfriend Michael is shot by her coworker and love interest Tony. So far, her relationships are lucky to last out an episode. Her longest lasting boyfriend, Ray, went on and off for a couple seasons before he proposed to her. Then she arrested him for murder.
Agent McGee is also an excellent fit, as (with the exception of Abby) anyone he's even shown an interest in either dies or turns out to be the murderer-of-the-week. The cute computer programmer he flirts with for half an episode is strangled right in front of him. A Petty Officer he had a thing for in training turns out to be a lesbian AND is the episode's killer to boot. A cute girl he picks up in a coffee shop ends up being a foreign national who holds him at gunpoint for information and is shot seconds later. His most recent girlfriend was caught in a terrorist bombing, lost the ability to walk, and then took a transfer to Dubai.
From 24, we have Jack Bauer. Let's go down the list: Teri died, Nina was The Mole, Kate dumped him, Claudia died, Audrey was made to believe Jack had died, Diane broke up with him when he got back together with Audrey, who was then tortured to insanity, and Renee bites it less than an hour after sleeping with Jack. Geez, this guy can't catch a break.
It extends beyond just Jack. Tony had also been in a relationship with Nina, then had Michelle divorce him, then get murdered shortly after they remarried and she became pregnant with their son. Every president that is shown with an on-screen spouse ends up divorced after one season David Palmer after Season 1, Charles Logan after Season 5 (though he first appeared late in season 4), and Allison Taylor after season 7, and David Palmer had a later girlfriend break up with him due to an inability to handle the limelight of being involved with the president. Audrey Raines was on the verge of reconciling with her husband when he died from injuries sustained when he took a bullet for Jack, the man she'd been involved with during her separation from him, then is led to believe Jack is dead, then finds out he's alive just before he gets taken prisoner by the Chinese and never really learns otherwise due to the aforementioned torture she gets after going to China to look for him. Even Kim had this for awhile, as her first boyfriend was incarcerated, her second broke up with her after losing a leg as the result of her actions, and her third broke up with her after she was led to believe that her father died and may or may not have died offscreen a few seasons after his final appearance. She at least finally gets a happy ending, getting married and having a daughter at some point between seasons 6 and 7.
Audrey, after finding Jack was alive, gets taken out in the last episode of the mini-series.
Both of Hercules' wives died on Hercules: The Legendary Journeys. The first after living long enough to give him three children (who were killed along with her) the second after they were married for probably a few weeks. Both murdered by angry gods. Iolaus had a wife in the first film length episode, but she died (supposedly in childbirth) and was never mentioned again.
The writers of Wizards of Waverly Place have played with our expectations by leading us to believe that Justin and Juliet, as well as Mason and Alex, might actually go the distance. Mason goes from werewolf to full wolf, and Juliet gives new meaning to "showing her age".
All of Gabrielle's male love interests on Xena: Warrior Princess end up either dead or disappeared by the end of the episode.
With the exception of Hercules, Xena's male lovers didn't fare too well, either.
Ares seemed to be going pretty strong, too. Although it's debatable whether he actually slept with her, just granted her "boons" for being a great Lady of War and explained it in a sleazy way, or if he's actually her father. Although, knowing Greek Mythology, that last one wouldn't have stopped him.
His new series counterpart, Lee "Apollo" Adama is likewise cursed. Starbuck married someone else, then Ascended to a Higher Plane of Existence. Dee left him, then committed suicide. "Black Market" mentioned something about a pregnant girlfriend who died in the Cylon attack, but we're not certain that episode is canon.
Chief Tyrol doesn't fare any better.
First love interest: Tory Foster. They forget all about being in love and planning to get married after Cavil kills them and resurrects them with Fake Memories. She kills Cally and he kills her for it.
Second love interest: Boomer. She turns out to be a sleeper agent and is killed by Cally (but resurrects). He verbally hates on her. They are on opposite sides on New Caprica, but don't see much of each other. When they next meet, she manipulates him into setting her free so that she can intentionally betray the whole ship. He verbally hates on her, again, and never sees her again. Though she redeems herself, she is killed right after. Oh, and he's kind of her dad, anyway.
Third love interest: Cally. She shot Boomer. She was sleeping with Hotdog before she got together with the Chief, and does not tell Chief that Nicky isn't his biological son. They argue a lot, but are genuinely in love. After finding that he is a Cylon, she attacks him and tries to commit murder-suicide with Nicky. Tory talks her out of it to get Nicky and then kills her. He verbally hates on her, and beats her when she picks the wrong time to wake him up.
According to Word of God, averting this trope is part of the reason for the creation of Laura Roslin's character in nBSG. Ronald D. Moore wanted a female co-lead to counterbalance Adama, so that way the show wouldn't spend time trying to pair Adama with various women of the week.
Lex from The Tribe has a curious version of this: women can and do survive sleeping with him, but if they say "I do" they're signing their own death warrant. First wife Zandra is killed in the explosion at Eagle Mountain (end of season 1), second wife Tai-San is kidnapped by an invading tribe and assassinated (off-screen) when her attempt to infiltrate them is revealed (season 5), and third wife Siva is shot dead by her own sister (end of season 5).
Sara Pezzini from Witchblade is a very bad woman to court. In a short two seasons:
Conchabar, a man she loved in a past life, gets stabbed through the chest with her own Witchblade when she gave it up in a bid to save his life.
He then gets resurrected thanks to the Reset Button Ending, only wind up in a coma shortly after meeting her again. He was also kidnapped and shot in the leg while unconscious. He had not regained consciousness by the time the series ended.
Jake, her partner who has expressed romantic interest in her, gets strangled and killed by an evil clone of Ian Nottingham. He also got beat to a pulp surprisingly regularly on the show.
Daniel lasted even shorter than any of the other men in her life, since he tracked her down with the express purpose of getting her to kill him, as she's the only one who can. He didn't plan on falling in love with her, but he doesn't let that stop him.
Gabriel finally makes a move in the season two finale. He promptly gets possessed by Kenneth Irons and helps try to kill Sara. It's implied in the ending that he is either still possessed or there are side-effects.
Any of Charles Bartowski's love interests on Chuck. If the episode doesn't fixate on the UST with his handler Sarah (and sometimes even then), his disastrous love life will be a major plot point. A former girlfriend gave him another chance, only to be revealed as a spy for Fulcrum. A nice, cute, normal girl he meets can't deal with his second job as a spy. In the course of his work as a spy he has met several Vamps. Chuck is a Hollywood Nerd, so this phenomenon is remarked upon in-universe even by those who don't know about the spy work.
On The Mentalist, Van Pelt has had two love interests. The first turned out to be the son of a man whose life Jane had ruined, and tried to kill her and Jane. The second, whom she was engaged to, turned out to be one of Red John's friends, and tried to kill her and Lisbon. She had to shoot him herself.
Thankfully, the Time Skip allowed her to get married to her partner Rigsby. They now have two kids (one of their own and one from Rigsby's previous relationship) and their own successful security firm. The story eventually had them Put on a Bus to their Happily Ever After.
Something of a reversal/subversion of this trope: the series Life On Mars ends with main character Sam Tyler returning to the world of the story - and his love interest - by jumping off a rooftop and committing suicide. The name of said love interest? Annie Cartwright.
Avon of Blake's 7 suffered from this one; Paul Darrow, the actor playing him, says he became known as the "kiss of death". In fact one actress was truly furious to learn that he was going to kiss her, because she had been hoping to stay on for another episode.
As mentioned in the description, Alias's Sydney Bristow is particularly adept at this trope right out of the gate (sorry, Danny).
Jeremy in The Vampire Diaries has dated two people, both of whom died shortly after they met him, one twice. A girl checked him out once, and died. The person he's currently interested in is in the process of Casting From Hit Points herself to death, although she's a major enough character that she might well survive. He acknowledges this, telling his current love interest shortly before she almost dies again,
Jeremy: You know, I don't have the best luck in the girlfriend department.
Averted for the moment as his third girlfriend isn't dead yet, which is surprising for The Vampire Diaries as Anyone Can Die. His previous girlfriends aren't exactly out of the picture yet either, it seems, as they return as ghosts.
In the fourth season finale, the third girlfriend (or ex-girlfriend) dies trying to bring Jeremy back to life.
In The Avengers, one episode featured a race where participants were assigned to partners. Steed's partner was a young woman who recounted the tragic deaths of her many husbands, apparently by bad luck, as Steed grew more disconcerted each time she revealed a new former spouse.
Mission: Impossible was inconsistent about this. In one episode Jim Phelps fell in love with a beautiful double agent who died protecting him from the bad guy. When the same thing happened to Paris in a later episode, he was able to rescue her at the end, though she was never seen again.
Alma Garret (Molly Parker) on Deadwood. First, her husband gets murdered. Then, she and the sheriff start a really hot and heavy affair, but his wife shows up. So, she gets married again, and her new husband is murdered as well.
Mark Gordon in Highway To Heaven meets a woman, falls in love with her, and she dies of cancer, all in one episode.
Bo in Lost Girl has this issue as she is a succubus who drains her partners' life force. Subverted later on when she learns to control her powers and finds a love interest with a Healing Factor.
Jason Stackhouse in True Blood. To be fair, this IS a plot point. The town murderer keeps attacking the women he's been with.
Played with by Cadet Annie Metford in the live-action Police Academy series, whose newlywed husband died in their bed while they were making love. All subsequent attempts of anyone getting close to her result in serious bodily harm. Fortunately for the guys, it seems that a direct sexual relationship and/or marriage seems the only way to trigger this trope to its fullest extent.
Amaka Okoh from Tinsel: first her husband, Reginald, then her boyfriend Sunom Idibia.
All the False Romantic Leads for Sarah "Mac" Mackenzie from JAG died one way or another. The Cartwright Curse also affected Harmon "Harm" Rabb, Jr. too, but with the difference that only one of them died.
In the old Mike Hammer series any woman he showed an interest in invariably either died or turned out to be a villain. Lampshaded by the DA who once referred to him as "the angel of death"
On Weeds, if you marry Nancy Botwin you will die. It's an axiom of nature.
Susan Ivanova of Babylon 5. First lover to appear on the screen survives but turns out to be an evil neo-Nazi terrorist. Second gets her personality permanently overwritten with an evil implanted artificial personality just after they slept together for the first time, and may possibly die offscreen afterwards. Third dies in a Heroic Sacrifice by using an alien medical device to give her all his Life Energy when she's mortally wounded. And if Claudia Christian hadn't left the show, she'd then have moved on to a cult leader who killed himself with all his followers.
Stringfellow Hawke points out in the pilot episode of Airwolf that he's afraid of getting into a relationship with a woman since every single one of his former girlfriends died.
Peter (her true love; killed by her in wolf form before she knew what was going on)
Quinn (a fellow werewolf who teaches her to maintain control; killed by guards who are after Snow)
Billy (a man who had a crush on her in Storybrooke; killed to frame her).
Heroine Emma isn't doing much better. So far, out of the five potential love interests three have been killed (with one revived as a child) and another turned out to be a monster in disguise sent after her.
On the sitcom Wings, Fay has buried three husbands named George. In one episode she meets a nice man named Lyle, and they decide to get married since they're both old and don't have a lot of time left. Right before the wedding, she finds out his name is actually George (Lyle is his middle name) and panics because she's afraid she's cursed. He starts trying to insist otherwise, despite suddenly starting to lose his vision and all the feeling down the left side of his body. The moment she calls off the wedding, he recovers.
The protagonist of Spartacus: Blood and Sand has a bad case of this. Basically, if you are a woman and he is even remotely into you, your odds of survival of extremely slim.
Ted Mosby and Barney Stinson have gone through so many woman and so many relationships it isn't funny. Ted seems to think that pretty much every girl he dates could be "the one", so he spends much of his life searching for "the one". Barney, on the other hand, is definitely not looking for "the one". Although it's confirmed that he does get married.
One Life to Live 's Bo Buchannan had so many of his love interests killed off that when it was obvious that he was going to be paired with new character Nora—thanks to their Belligerent Sexual Tension—fans actually pleaded for them NOT to be paired, despite their excellent chemistry, because Nora had rapidly become a favorite and fans did not want her to meet the fate of Bo's other lovers. Luckily, the writers decided it was time Bo had some luck in the romance department and Nora was allowed to live.
Oliver: Sarah Lance dies after her cheats on her sister with her, Helena Bertinelli starts killing everyone who gets in the way of her killing her father until Oliver tries to put an arrow in her, McKenna Hall gets shot by Helena and has to move to Coast City to get the physical therapy she needs and Shado is shot in the head due to a Sadistic Choice. Though, subverted (so far) with Sarah, who's revealed to be alive.
Laurel: Oliver gets stranded on an island for five years and Tommy is killed saving her life. In season two she starts dating Sebastian Blood who turns out to be the villain Brother Blood. The Ravager kills him in the season finale.
Being 5000 years old, Methos on Highlander is the king of this trope. Aside from Cassandra, who was more a slave, he had 60 wives through the years. The other immortals fall into it too (see Film)
Jesse Pinkman in Breaking Bad lost both of his love interests, Jane and Andrea, throughout the series.
Hiro Nakamura of Heroes has absolutely zero luck in the love department. His first love interest, Charlie, ends up killed by Sylar almost the moment they figure out they have something. He tries to use his time travel to save her, but ends up six months in the past instead, setting up the Tie-In NovelSaving Charlie (which reveals that most previous women in his life have simply opted to avoid interacting with him whenever they can). Hiro takes The Slow Path back to the present and forms a relationship with Charlie over those six months, but then has to allow her to be killed again because her death is what caused him to take that leap back in time in the first place. Hiro's Second Love, Yaeko from Hollywood Medieval Japan, doesn't actively die on screen, but he can't be with her because that would break the timeline and he might end up his own ancestor - oh, and there's the whole deal with his hero Kensei being extremely jealous (did we mention Kensei is immortal and takes The Slow Path back to the present to hunt down Hiro for daring to steal his destined girl?). Then, Hiro manages to figure out a way to convince Sylar to actually save Charlie from an aneurysm instead of killing her for her Photographic Memory, but Charlie gets ripped out of his life again by evil carnie Samuel and sent back to the 1940s using his own time traveler - but, without knowing where or when she ended up, Hiro couldn't save her. She ended up building her own life without him, only meeting him again briefly when she's dying of old age.
In the 1970s BBC series Secret Army, both of Natalie Chantrens' love interests — Francois and Nick Bradley — died horrible deaths.
According to Pop-Up Video, the video for Paula Cole's "I Don't Want to Wait" is about an immortal woman who keeps outliving her significant others.
Which is ironic because in the song lyrics her significant other comes home from the war and lives to see his granddaughters.
In The Bible (well, the Book of Tobit, which is in some Bibles) a woman named Sarah has a bad case of this—she is married seven times, but each groom dies before the marriage can be consummated. It turns out a demon named Asmodeus is in lust with her, and killing all his competition; the hero and her cousin, Tobit, marries her and is able to drive the demon away following instructions from the disguised Archangel Raphael. He survives the wedding night while Raphael definitely seals Asmodeus away, and he and Sarah live happily from then on.
In another example, from the Book of Genesis, a woman named Tamar is married to Er, but he dies without leaving any heirs, so she is married off to his younger brother Onan. Onan doesn't want to father children on someone else's behalf, so he uses coitus interruptus, which his death is attributed to. Their father Judah, has one young son named Shelah left, and fears for Shelah's life since he believes Tamar to be cursed; Judah tells her that he'll give Shelah to her when the boy grows up... but when Shelah grows up, he is not married off to Tamar as promised, so she impersonates a shrine prostitute and sleeps with Judah so she can get pregnant and continue the bloodline, with the precaution of taking some of Judah's belonging as "payment" — which she shows to Judah before explaining herself. Judah realises Tamar is in the right and accepts responsability, with Tamar's twin kids being aknowledged as part of the family.
In "Doubt Academy', Misaki Watanabe has lost two boyfriends Jack Myōji and Kuu Fukubaka to Monobear's killing game.
In fact, just 'if Otacon likes you'. Look at what Snake went through in four. Sure, it didn't KILL him. Yet.
This seems to happen in Max Payne too except if you pass the game on Dead on Arrival, then Mona lives. Sadly non-canon in Max Payne 3.
In World of Warcraft Jaina Proudmoore's luck SUCKS. Seriously. She was desired by Kael'thas Sunstrider for quite some time. Nothing ever came of this, as she was already beginning a relationship with Prince Arthas Menethil. If you've only played World of Warcraft, you may know him as the Lich King. Kael'thas himself was utterly crazy by the time of Burning Crusade. Given all that, this does not favor her most recent love interest (the blue dragon Kalecgos) at all.
Zevran from Dragon Age: Origins. His previous love interest, Rinna, died. Plus the scores of romantic partners who either died or were murdered from his time in the Antivan Crows. You can also romance him as a Warden who commits a Heroic Sacrifice at the end of the game, meaning that every significant lover he's ever had is dead.
The Mass Effect series contains a very unique and interesting example since the curse is actually an unintentional (or intentional) result of certain decisions the player makes. It's only played straight if you leave your love interest to die on Virmire in the first game and if your choices gets your second love interest killed during the suicide mission in the second.
Not just love interest, but anyone who is close enough. If you really, really mess up in Mass Effect 2 both your squad and ship crew die. Shepard's background options: If you really want to push this forward she/he has upon that point lost both her/his family in a slaver raid and marine friends in a Thresher Maw ambush.
Every woman in the series ends up getting killed, usually in an ignoble and pointless manner. It takes until the 4th game in the series for a female character to survive to the end, and she gets shot in the gut about 3/4ths of the way through. The 4th game is a Continuity Reboot anyway, so perhaps one of the things discarded was the series's major Stuffed into the Fridge trend.
Fire Emblem: Shadow Dragon has the in-universe legend of Artemis' Curse - whenever a hero takes up the eponymous Fire Emblem to save the world, he is doomed to never be with his true love. This goes even worse for the direct descendants of the Archanean royal family, who are cursed to forever live lives of tragedy and doomed relationships due to the founder of Archanea being a thief who stole the Fire Emblem from its sacred temple and sold its pieces to fund his rebellion against the Dolhrian Empire. Until Fire Emblem Awakening, that is.
Lon'qu from Fire Emblem Awakening deconstructs this. His first friend was a young girl his age, who was killed by bandits (and apparently in an Heroic Sacrifice to save him) while he couldn't do anything to rescue her. As a result, he started to believe he suffered from this trope, to the point where he developed gynophobia: he does not hate women per se, but cannot bring himself to get close to them out of the deep fear that he will get them killed. The only girls he'll approach without much trouble will be either his girlfriend/wife and a prospect daughter fathered by him.
In the PC game series Dark Parables, Prince James suffers from a form of this in the second game. He's The Frog Prince, and he's immortal... so he's had to watch everyone he loves die, including the five fairy tale princesses he married.
Elf from Schlock Mercenary. She even managed to kill off Captain Tagon in an alternate timeline. At one point, several other troops point this out when a Mauve Shirt demolitions expert tries hitting on her. Guess what happens to him...
To discredit this, she gives a kiss to each of the other men on her squad and then tells them that now they are doomed they can bloody well start marching. Apparently, that didn't count since they survived. (Except for one who died much, much later.)
Almost immediately after Kevyn dated her, he got killed, and only his blood nanites managed to bring him back from the dead.
Considering that he keeps a running count of the number of times he's cheated death, this is similar to the Stargate example above, except canon.
To wit, Elf is now five for six for killing men she's kissed. As has been mentioned, Tagon was an alternate reality, and Kevyn got better, but the only survivor of Elf's kissing (Nick) had a good chunk of a story-arc dedicated to "breaking the curse."
Torg from Sluggy Freelance has a pretty bad track record when it comes to girlfriends. One was an evil vampire who he had to kill. Another is a psychotic and assassin who keeps dying and coming back. Another was driven insane after being traumatized by satanic kittens. And a fourth was killed by a demon lord trying to catch him. With all this Torg's inability to tell Zoe he loves her is perfectly justified.
Eventually Zoe came to the realization that not only was Torg in love with her, she loved him back! Which directly resulted in Oasis using pyrokinetic powers and almost killing her. She spent some life support. She was completely restored, except for the memory of the day in which she realized that she and Torg were in love and ended up getting incinerated by Oasis.
Sollux Captor from Homestuck can be said to suffer from this, as both Aradia and Feferi have died at least once during the story. Feferi has, so far, stayed dead, but Aradia got better eventually—but not before dying twice.
Really, the poor guy can't catch a break in this regard. Aradia's first death involved Vriska mind-controlling Sollux into murdering her, and her second death involved her robot body exploding right after she gave Sollux a (seemingly) final goodbye hug—though, as mentioned above, she recovered. Feferi, meanwhile, died at Eridan's hands, having rushed to avenge Sollux after Eridan blinded him.
Sapphire: Somewhat. Ivanka gets killed, but only five years after she marries Alec, which in turn was four years since they first met.
Possibly genetic with the Water Tribe siblings on Avatar: The Last Airbender: Katara's love interest, Jet? Turns out to be evil, reforms and ends up dead. And Aang is killed or nearly so in the season two finale, but then is brought back to life with magic water. Sokka's love interest, Yue? Died to save the Moon Spirit by becoming it herself. His other love interest, Suki? Ended up tortured in a Fire Nation prison, with the audience and the main characters not even sure if she was alive. But she was! Hooray!
One wonders why Toph seemed to have an unrequited crush on him at times. I mean, you'd have to be blind not to se-... Oh, right. Sorry.
It even traces back to their parents and grandparents! We never hear a word about Kanna's first husband, and Hakoda's wife Kya... well...
Given none of them lose more than one, that's more like "man, this setting with all its war and attempted genocide has a high mortality rate!"
Zuko, on the other hand, has something like three Love Interests, although only one of them's at all serious, and they're all fine, although he stole Song's ostrich-horse and got Mai sent to prison.
The Boondocks episode "It's Goin' Down" parodies 24. The character known as Jack Flowers had this problem with his relationships: The first woman had her head sliced off by a sword, the second woman was flung off a building only to explode by a bomb strapped to her before hitting the ground, and the last woman was tied to a rocket.