Considering the nature of this trope, expect massive spoilers unmarked.
In Dragon Bones, Tosten, the younger brother of the protagonist, Ward, is driven to suicide by his abusive father. Ward finds him just in time to save his life and take him to another town, where their father can't find him. Also, Oreg, who was Made a Slave and could only be killed by his owner. He tried to provoke at least one of his owners into killing him. Unfortunately, the guy was clever enough to have someone else beat the shit out of Oreg, from which he recovered due to the near-immortality.
Thirteen Reasons Why begins with Ordinary High-School Student Clay receiving a series of tapes from his classmate Hannah Baker, who'd recently killed herself. The tapes are her suicide note, and if you've received them, then you're one of the thirteen reasons she decided to end her own life. The story follows Clay as he listens to the tapes and follows her story. It turns out that Clay was a Nice Guy she featured on the list simply so she could apologize to him for having treated him strangely at a party.
Hannah: It's like that one song: One of these things is not like the others.
In Khaled Hosseini's And The Mountains Echoed, Nila Wahdati commits suicide. It's heavily implied that she felt horribly guilty for allowing her adoptive daughter Pari to be kidnapped from her rightful parents and lying to her for her entire life that she was Pari's true mother. In addition, she was jealous of Pari since she is fertile and Nila is not, and that Nila constantly relied on her sexuality to sustain relationships with men but could not give them anything meaningful in return, namely a child.
In Faulkner's Absalom, Absalom!, Bon essentially commits suicide by continuing to travel with Henry to his supposed wedding, because he cannot accept that Henry would murder him rather than let him pollute the Sutpen line with his mixed blood.
The character Cass Anders shoots himself in the Callahan's Crosstime Saloon short story "Fivesight" because he sees the future, but cannot change it or what he tries to prevent ends even more disastrously. He crossed his Despair Event Horizon when he foresees but fails to prevent his stepson's death by car accident.
More than one patron of Callahan's—including the narrator, Jake—is in a suicidal frame of mind the first time they walk in the door, since it's a place people find when they really, really need it.
This was how Brave New World ended. The protagonist who never had a happy life at his old place but adopted their beliefs moved with Bernard back to London. London is like all the world except where said protagonist came from and maybe the islands (unless those fall under Released to Elsewhere). It is a Crap Saccharine World where there is no free will and everybody is on drugs all the time. John eventually undergoes a Heroic BSOD which eventually makes him go against everything he believed in and cave into the peer pressure. He hangs himself in an act of honor.
In House of the Scorpion, Tam Lin drinks wine only he knew was poisoned as an atonement for planting a bomb that accidently killed twenty school kids.
In Emily Bronte's Wuthering Heights Catherine purposefully makes herself sick (and later dies) just to spite the two men who love her.
In G. K. Chesterton's Paradise of Thieves, Father Brown discovers that someone was carrying a bottle of poison. Discovering who is it takes a little longer.
Trilby has the titular character, having left her friends and supporters out of shame, contemplate throwing herself into the Seine; at the last moment she gives up and returns to her evil mentor Svengali. She doesn't say whether that's worse or not.
In Darkness Visible it is eventually revealed that the incident at the Marsh house was not a random attack. After years of brutal abuse by her husband, Mrs Marsh told the Dark Tide to open the Thresholds, knowing it would kill her, and intending that it would Mercy Kill her children at the same time.
In The Moth Diaries, Ernessa may or may not have committed suicide by slitting her wrists after her father's death (also a possible suicide), which act could have made her a vampire, if she was one. The narrator theorises this - no, she states it as a matter of fact - in one of the very last entries in her journal before she tries to burn down her school; as her mental health was already deteriorating quite early on, we are left unsure. The narrator also contemplates this act, but doesn't go through with it. Her father did this too, which did leave you wondering whether the narrator was imprinting her past onto Ernessa, and fantasising about ending her life in the same way.
In The Mirror Crack'd from Side to Side, the killer is found dead of an overdose after The Reveal. It is implied in the book that this was because the killer's spouse had done it to prevent further murders.
In the two Hercule PoirotSame Story, Different Names short stories "The Market Basing Mystery" and "Murder in the Mews", the supposed murder victim was Driven to Suicide, and someone close to them dressed the scene up as a murder to punish the person they felt was morally responsible for the death.
The Mr. Quin stories have lovers in dire straits as an integral part of the premise; consequently a disproportionate number of them include somebody admitting, explicitly or tacitly, that when Mr. Quin took a hand in their problem they were this close to ending it all. The central character of "Harlequin's Lane" goes through with it in the end; when it comes to love, not all problems have a neat solution that includes everybody.
In Lord Dunsany's short story The Jest of the Gods, the title characters created a king's soul containing more pride, strength, and ambition than kings ordinarily had, then sent the soul to be born as a slave. Their jest backfired when the soul grew up and was Driven To Suicide, which they hadn't expected. Leads to a Crowning Moment of Awesome when he then faces them down.
Esther Greenwood in The Bell Jar attempts suicide a number of times before being hospitalized. Given the time period (The Fifties), Esther is terrified of the common reality that a married woman spends the rest of her life in the kitchen and giving up everything she ever worked towards. After finishing college, she has no idea what to do with her life and becomes saddened by the fact that "the one thing [she] was good at was winning scholarships and prizes and that era is coming to an end." After trying to slit her wrists in a warm bath and trying to swim out into the ocean, she crawls into a hole in her basement and downs a bottle of sleeping pills.
In The Hunchback of Notre DameQuasimodo kills himself, due to either being related to or participating in the deaths of everyone he loved.
In Dean Koontz's Odd Thomas, Odd's mother, who is incapable of any responsibility whatsoever, threatens suicide with a gun any time anyone asks her something she doesn't want to deal with. She does this even to Odd as a child, which is certainly emotional abuse.
Well, if that isn't abuse, putting the barrel of the gun to his eye so he could see the bullet, and threatening to kill him, certainly is.
In Stephen King's IT, Stan Uris breaks and is Driven To Suicide when faced with the prospect of returning to the Town with a Dark Secret. Dorsey and Eddie Corcoran's step-dad also commits suicide after he's released from prison for beating Dorsey to death with a ball-peen hammer.
Dayna Jurgens from The Stand impales her neck on a piece of glass to prevent Flagg from interrogating her. Nadine Cross also does this to prevent Flagg's offspring from being born, and she's probably Ax-Crazy by this point. Rita (Larry's first traveling companion) and a number of the early survivors also commit suicide.
Several of King's other characters are also Driven to Suicide. The lady in the tub in The Shining; the patient who eats himself to death in Dreamcatcher; the protagonist in "I Am The Doorway," and so on.
At the opening of Garth Nix's Lirael, Lirael decides to commit suicide at the age of fourteen, having not received the Sight and therefore still a child in her cloistered world. She climbs to a ledge in a Paperwing (airplane) hangar to jump to her doom. She is stopped when a Paperwing arrives, and witnesses the ensuing plot-relevant conversation. The other Clayr find her and deduce what she was doing. They convince her that there is still hope she will gain the Sight, and promptly erase her memory of the plot-relevant conversation.
She tried again in the ensuing years, but was talked out of it by her companion, the Disreputable Dog.
Applied with a twist in Edward Arlington Robinson's famous Richard Cory. The bulk of the poem is a glowing but superficial description of the regal title character. In the final line, he shoots himself without warning or explanation; we see the suicide, but (uncommonly in fiction) we receive little sense of why he was driven to it.
In Dorothy L. Sayers' Lord Peter Wimsey stories, particularly the earlier novels, this is a convenient way of disposing of those responsible for tragedies without the need for a trial.
Whose Body?: The killer writes out a detailed confession in a long suicide note addressed to Lord Peter, but is arrested before the suicide can take place.
Clouds of Witness: The victim was a suicide whose only note was a letter to his ex-mistress, who didn't bother to read it properly. Much later, in Gaudy Night, Lord Peter indirectly refers to this case as the time when he appeared to have the choice between hanging his brother or his sister; Harriet Vane said that in one of her own mystery stories, etiquette would demand a written confession, followed by poison for two in the library.
The Dawson Pedigree (a.k.a. Unnatural Death): The killer commits suicide in jail at the end of the story.
The Unpleasantness at the Bellona Club: The killer is persuaded to write out a confession and commit suicide at the end of the story.
Murder Must Advertise: The killer of the first victim - the person that Lord Peter originally set out to find - commits Suicide By Criminal as an alternative to trial and conviction.
Arguably, this happens in The Nine Tailors.
In Josephine Tey's The Singing Sands, the egocentric killer opts for a dramatic suicide and a long-winded suicide note to a Scotland Yard investigator, assuming that the murder has been a perfect murder that could not have been detected or proved and wanting to go out in a blaze of glory. Wrong on all counts, as it happened.
In J. R. R. Tolkien's The Lord of the Rings Denethor attempts to burn himself and his son on a funeral pyre when he believes the battle against Sauron is hopeless, and that his son is dying through his own fault. He succeeds in killing himself, but his son is saved just in time.
Éowyn also rides into battle wanting to die after being convinced that she'll spend the rest of her life taking care of her declining uncle as the House of Éorl becomes more and more dishonorable.
Fingolfin challenges Morgoth to single combat (he does pretty well, but there was no way he was going to win, and he's smart enough that he must have known that);
Niënor finds out that she's married to and pregnant by her long-lostbrother, and jumps off a cliff;
Túrin finds out that he's married and impregnated his sister (and that killing all those other people may also have been a mistake), and doesn't so much fall on his sword as politely ask it to kill him;
Húrin, who has been forced to watch his son marry and impregnate his daughter and both of them commit suicide (and finding his wife again after decades of separation only to have her die almost immediately), despairs and casts himself off a cliff;
Elwing jumps off another cliff although she survives, carrying a Silmaril, while Maedhros was attacking her city to get it;
And later on, Maedhros realizes that killing all those people was definitely a mistake, and jumps off a fourth cliff. This is after a much earlier I Cannot Self-Terminate moment while he was hanging off a different cliff.
In The Bible, having lost a battle as well as his beloved eldest son Jonathan, King Saul falls on his sword when his armorbearer refuses to kill him, figuring it would be better to die by his own hand than to be mistreatedand killed by the Philistines. An Amalekite, attempting to ingratiate David, takes credit for killing his old enemy, but is executed for his troubles as the new King David goes into a Heroic BSOD, ripping his clothes and screaming for the deaths of Saul and Jonathan. This makes this trope Older Than Feudalism.
Samson prays that God will give him strength to bring down the Philistine temple — and that he will die there and so escape.
Racked with guilt for having betrayed Jesus, Judas Iscariot returned the reward money and hanged himself. (Matt 27:3-5)
When an earthquake struck the jail at Phillippi, the keeper of the prison was going to kill himself, thinking the prisoners had fled, and he knew he'd probably die if that happened. He was stopped by Paul, one of the prisoners.
In House of Leaves, Holloway Roberts goes Ax-Crazy exploring the labyrinth, shoots both of his fellow explorers, and runs around inside the labyrinth talking into his portable camera, constantly repeating his name and where he was born. Several days later he finally shoots himself, having gone insane from fear of something he perceived was following him.
The legendary Roman matron Lucretia, most famously memorialized in William Shakespeare's poem The Rape of Lucrece, commits suicide after being raped.
In Atlas Shrugged, after Cheryl Taggart realizes that her husband is evil and willing to destroy anything she would achieve for her own interest, and that the world is ruled by people just like him, she races to throw herself into a river.
In Sandy Mitchell's Ciaphas Cain novel Cain's Last Stand, when Donal's freedom from mind control is lost as Jurgen steps away, he turns his gun on himself rather than attack Cain. Later, the Battle Sisters whom Varan brought to his meeting with Cain are also freed by Jurgen's nearness, go insane realizing what they have done under his influence, and commit suicide.
Later, Fulgrim realizes how great his betrayal is when he kills Ferrus Manus. He goes to kill himself. His sword says it's too noble for him, and tricks him into accepting possession.
In Lee Lightner's Warhammer 40,000Space Wolf novel Wolf's Honour, when Ragnar and Torin] speculate about the causes of the slow turn to wulfenencroaching on their minds, Ragnar thinks it may be his influence. Torin dissuades him, and is not amused when Ragnar says that it would be much better if he could end it by shooting himself.
In James Swallow's Warhammer 40,000Blood Angels novel Deus Encarmine, when the second Last Stand looks even more devasted than the apparent first, Turcio speaks of their defeat. Only when Arkio offers him a knife to cut his throat with does Turcio rouse himself to fight again.
In Deus Sanguinius, Inquisitor Stele plays on Rafen's fears — that he overshadows his younger brother and is jealous of him — to convince him that he has to free Arkio by killing himself. Only a literal vision allows him to throw off the mind-witchery.
In Gav Thorpe's Warhammer 40,000 novel Angels of Darkness, the Dark Angels are trapped in a fortress because if they leave it, they will release a horrific virus on the planet and its population, but their suits can not last as long as the virus. They fear what desperation will make them do and think it better to die together, quickly, so they each hold a bomb and have Boreas push the denotator to kill them all.
This trope applies to the story of The Bloody Baron from Harry Potter and the Deathly Hallows, who did precisely this after killing his lover, The Gray Lady, in a fit of rage. Both of them return as ghosts afterward.
From the same book, Hermione points out that the wizard or witch who split his/her own soul to create a Horcrux must feel deep and genuine remorse in order to fix their soul fragments back into one whole piece. The drawback? Said wizard or witch may be overwhelmed by the pain of it to end up with this trope.
Quentin Compson in The Sound and The Fury commits suicide because he's unable to cope with living in a world where he doesn't belong anymore. Quentin was born and raised on the values of the Old South, particularly about how women are suppose to be virtuous and upstanding. He begins to lose touch with reality when his older sister, Candace, begins to sleep around, destroying his aforementioned belief of women, his father preaches nihilism, and sees the Old South fading away.
In Lonesome Dove, After the town has become a ghost town, Xavier tragically locks himself into the barroom and then burns it down so he can't escape out of loneliness.
In Isaac Asimov's story "All The Troubles Of The World", Multivac comes uncomfortably close to destruction because of a seemingly random act — a potential disaster considering how much of the work of maintaining civilization has been dumped onto the computer. The story ends with Multivac being asked what it itself wants, and replying "i wish to die" — implying that the "random act" was a suicidal plan by Multivac that failed... this time.
In Everything Is Illuminated by Jonathan Safran Foer, Alex's grandfather commits suicide after 'Jonfen' leaves, being confronted with his past , where he saved his life and his son's, at the expense of his best friend's, at the hands of the Nazi's. To bury his guilt, he built himself an anti-Semitic persona, despite being Jewish himself. This is one of the few differences between the book and the movie, where in the movie he does so before he leaves. He is found in a bathtub by his grandson with his wrists slit.
An alarming number of John Le Carré's novels end with characters killing themselves, or deliberately allowing themselves to be killed.
The Spy Who Came in from the Cold ends with Alec Leamas allowing himself to be shot by East German border guards rather than escaping after his girlfriend is killed.
A Perfect Spy ends with Magnus Pym shooting himself in the bath.
Harry Palfrey, the narrator of The Russia House, throws himself in front of a bus in The Night Manager.
In The Tailor of Panama, Harry Pendel wanders out into the night, with every intention of being killed by invading US forces.
The Constant Gardener ends with Justin Quayle arranging things so that he will be killed in the same place by the same people who killed his wife.
In the Dragonriders of Pern series, the mental bond between a dragon and its rider is so strong that, should one die, the other almost invariably commits suicide shortly afterward. In the rare cases where the rider does not kill himself, he's left as an Empty Shell.
The book Seventeen deals with a seventeen year old girl who decides to kill herself in seven days if her life doesn't improve. Her best friend abandons her to become a model, her other friend is raped, she's convinced that she's never been good at anything except diving, and her boyfriend dumps her on the side of the road when she refuses to sleep with him. She goes straight to a bridge and jumps off. Halfway down, she changes her mind, puts her diving training into use, and swims to shore. The book ends without telling us if her life improves.
Brought up in one Doctor Who Expanded Universe novel. See, the Eighth Doctor of the novels is even more of a Cloud Cuckoolander than the Doctor usually is, and sometimes cannot tell the difference between TV and movies and Real Life. There's "a popular BritishSoap Opera" (likely EastEnders) which, if he watched it while in such a confused state, even after all the horrifying things he's seen traveling through time and space which have mostly only ever upset him a little, would so thoroughly convince him of "the sheer futility and misery of life" that he'd try to kill himself.note This comes up in a footnote, which is worded oddly, so it's not clear if he's ever gone so far as to try doing away with himself when faced with the endless tragedy that is life in Walford.
In The Heart is a Lonely Hunter, deaf-mute John Singer shoots himself in the chest after learning of the death of his best friend, Spiros Antonopoulos.
At the end of Dreamspeaker, Peter hangs himself, while the mute "He who would Sing" shoots himself in the mouth with a shotgun, in gruesome detail.
A famous example: in Goethe's The Sorrows of Young Werther, Werther shoots himself in the head to escape an unbearable love triangle (he is in love with a married woman). A semi-Bungled Suicide, in that he does not die instantly, but suffers for twelve hours before finally dying.
In I Shall Wear Midnight by Mr. Petty, who was Driven To Suicide after he went on a drunken rampage, bludgenoned his pregnant thirteen-year-old daughter and caused her to miscarry. Fortunately Tiffany arrives in time.
In L. Jagi Lamplighter's Prospero Lost, in the Back Story, Miranda had thought of killing herself when she thought Ferdinard had jilted her.
In Blue Lights And Long Nights by Les Pringle (about his experiences during his first 18 months as an Ambulance driver in Birmingham in the 1970's), he and a colleague were once called out, only being told that it was a "woman burned." It was worse; it turned out that a woman had been getting her kids ready, had just given them breakfast, and then went outside into the garden, poured petrol over herself and set herself alight. The children then noticed what was going on, and then ran after her mother, trying to douse her with cups of water. When the Ambulance arrived, the woman was little more than a charred corpse on the grass.
In Richard Stark's Parker, Parker's wife, Lynn, tried to kill him(and thought she did) and becomes wrought with guilt. When Parker comes back to find her, she is relieved at first. Considering it's Parker who comes back though, it doesn't last long. He doesn't even say a word to her before smacking her across her face. He doesn't care about her anymore, and only wants to find the man who betrayed him(and made Lynn try to kill him). She still loves him. She tells him that she can't sleep at night without taking pills. She thinks about how she killed him, and wished it was her. Parker offers a single piece of advice. "Take Too Many Pills." In the morning, when he finds her with an empty container in hand, he says "You always were dumb."
Jacqueline Wilson wrote an early (and now largely forgotten) novel called Falling Apart in which a teenage girl attempts suicide after being dumped by her boyfriend. She survives, and towards the end of the story her life seems to be improving; but the story shows that she is not over her ex, and hints that she might attempt suicide again.
In The Fires of Affliction, protagonist Khan Eilon's wife Sarah walked into the sea to drown herself after the death of their daughter.
In The Chalet Girls Grow Up by Merryn Williams, a sequel to the original Chalet School series by Elinor Brent-Dyer, Jack Maynard commits suicide after falling into serious financial trouble and Jo becoming increasingly absent-minded and difficult to live with (it is implied that she has Alzheimer's Disease.) This is part of the reason for the book's Broken Base, since in the original series Jack was a strict Catholic and would have considered it a terrible sin to commit suicide.
In the Gaunt's Ghosts novel The Armour of Contempt, Sabbatine Cirk kills herself with a poisoned dart due to having sold out the Gereon resistance to the Inquisition.
The Double Eagle spin-off novel has the suicide death of Major Heckel most likely cauesd by feeling of guilt and the strain of being an officer during an overwhelming Chaos offensive.
In Tad Williams's Memory, Sorrow and Thorn, reading Nisses' book will push you over the Despair Event Horizon and make you wish you were dead. The first person to read it flung himself out a window. The only other person we know to have read it was driven from a position of happiness and power to a life of wandering begging and shame and despair.
The overwhelming majority of vampires from The Vampire Chronicles end up this way, because they can't handle the continuous changes in human mindset and lifestyle.
Eddie Jacubois at the end of From a Buick 8. Just couldn't take his life anymore. It's speculated that the Buick may have had something to do with it, but it's unlikely.
Michael, in the Knight and Rogue Series, after developing fullblown magic and getting chased by a mob into a ice cold river during winter. When he pulls himself out he decides that, as a magic using freak, it might be better if he dies. Thankfully, he's rescued and convinced that there's nothing wrong with him before this idea can have any time to grow.
Things Fall Apart ends with Okonkwo hanging himself, unable to handle the changes wrought by the arrival of the Europeans.
Thanks to Leonard's unbridled optimism, his homeroom teacher threatens to kill herself with a pair of blunt scissors.
Training Officer Pam Jensen intends to soon, and Lane Dean is considering it.
A recurring theme or plot point in Norwegian Wood. By the end of the novel, four main or secondary characters kill themselves.
Sammy's suicide in the final year of high school in The Book of Joe has a huge impact on the lives of the characters around him and the novel essentially follows how his best friend is still struggling to deal with it, years since the event.
Sisterhood Series by Fern Michaels: Lethal Justice reveals that an elderly couple did this after Arden Gillespie and Roland Sullivan sucked up all their money. Isabelle Flanders admits that when everything around her just went to hell, she was one step away from committing suicide before Nikki Quinn came into her life. Hokus Pokus implies that Maggie Spritzer was on the verge of this, but Jack Emery intervened before anything really bad happened.
In Rick Cook's Limbo System, Ludenemeyer does this to avoid capture with his knowledge. Later, Jenkins implies to DeRosa that Dr. Takiuji had to agree to do this if need be to avoid capture to hide from spies that his actual plan was to substitute someone else for Takiuji and so prevent their having his knowledge.
Howard Van Horn does this is the Ellery Queen novel Ten Days' Wonder. This leads Ellery to prematurely conclude that the case is over.
A particularly manipulative example in The Monk Matilda swears that if she can't have Ambrosio or at least be near him, she will kill herself. This threat goes away later for reasons unexplained after he beds her.
In The Hermetic Millennia, this is the proper Chimera response to disgrace, such as losing your weapons. Lady Ivinia orders the Chimera men to commit suicide if they fail.
In Enchantress from the Stars Elana, a 14 years old girl from The Federation, is captured by colonists from The Empire. The colonists intend to bring her to their home planet, where she will be dissected and interrogated (and thanks to their tech, The Empire can extract any information they want). Not wanting to end like this, Elana runs towards the imperial rock-chever, intent on being crushed by falling debris. luckily, she is rescued Just in Time
Jeremiah Paulson from the Dale Brown novel A Time for Patriots.
A member of the Wakecliff family in A Brother's Price, Kareem Wakecliff, killed herself upon hearing about four catastrophic events happening to her family in one day: a shipwreck, a fire that claimed the lives of every family member under ten, smoke inhalation and burns killing the adults who'd tried to save them, and a Death by Childbirth.
It's also noted that men sometimes kill themselves to escape bad marriages.
In The Giver, Rosemary couldn't take the horrors of the memories she received, and applied for Release, which, unknown to most of the characters, is a lethal injection. And she knew exactly what it was—she asked to perform the Release herself. This prompted the community to add a new rule, in that future Receivers of Memory cannot ask to be released.
Tears of a Tiger had the protagonist Andy feel guilty for the death of Robert, one of his best friends, after a car accident he (Andy) caused. When his depression continued to linger (due to lying to get out of therapy sessions) and he started to grow distant from his friends and family, this concluded with Andy shooting himself with his father's handgun.
In Stella Benson's Living Alone, Sarah Brown whimsically thinks of this when in too much pain to move.
Sarah Brown wondered whether she could cut her throat with a hoe.
"Suicide while of sound mind," she said. "The said mind being entirely sick of its unsound body."
In A Desert Called Peace, the continual artillery bombardment of a Sumeri Army position by the Legion eventually drove a soldier to eat his gun.
An interlude in The Lotus Eaters tells of the High Admiral in command of the United Earth Peace Fleet around Terra Nova blowing his brains out after ordering the nuclear bombing of two Federated States cities in response to such weapons being employed against Yamato in the Great Global War, unable to get the images of FS victims out of his mind.
In Wody Głębokie jak Niebo, Arachne decides to commit suicide, when she is captured by Severo and faced with a Fate Worse Than Death. She tries to burn herself alive. It doesn’t work, because fire she wants to use is a demon and she ends up possessed by it.
In Dorothy Gilman's The Clairvoyant Countess, after Mazda Lorvale commits suicide in a mental institution, Lt. Pruden smuggles her suicide note out to Madame Karitska, which reveals many things about her.
Adventure Hunters: When Claude discovers his family died in the goblin raid, he falls on his sword.
Many of the people listed in the files retrieved during the Albanian operation in Choosers of the Slain have been quietly informed of the existence of the files, resulting in a lot of them committing suicide. Japanese businessmen in particular are said to have all killed themselves after being informed their activities were recorded.
In White Night, one of the characters that Dresden is trying to save is driven to suicide by one of the local White Court vampires that feeds off despair. It's implied that if the Denarians ever get their hands on Esperacchus (the Sword of Hope), they would try to drive someone to suicide in the hope that they would use the Sword as a way out, as that would be the ultimate expression of despair, which would destroy the power in the sword, and render it useless.
In Ghost Story the flashback reveals Harry himself is the one who hired Kincaid to kill him, in order to escape from being the Winter Knight. However, Uriel immediately draws attention to the mysterious shadow that spoke seven words to Harry, and purposefully pushed him to suicide. While Harry did try to kill himself, he was manipulated into it, so it's a bit of a grey area.
Subverted. Tessa makes the Magister think she killed herself so that he wouldn't get his hands on her power, but in reality she Changed into a woman who'd died by a gunshot wound seconds before the wound would prove fatal.
Played straight with Barbara Lightwood and her brother.
Prior to The Mortal Instruments, Celia Herondale killed herself when she heard about her husband Stephen's death, despite being pregnant at the time. Valentine cut her son Jace out from her body and raised him as his own.
In The Lords of Discipline: A minor character, Poteete, hangs himself in the first act of the book. This foreshadows when Pig walks in front of a train after he's expelled from the Institute a few months from graduation.
At the end of dystopian novel Natalie Mooshabr's Mice, poor and old widowed Mrs Mooshabr poisons herself and dies. It happens after The Reveal that she is rightful ruler of the oppressed country, Duchess Augusta, and she dies just before she ruturns on her throne.
Madame Bovary: Emma poisons herself with arsonic, feeling unloved and misunderstood by her husband and lovers and unable to pay her debts she owes to a usurer. She expects her death to be romantic and dignified, but it is anything like it and she suffers horribly.
Anna's lover Vronsky feels suicidal about half in the story but his attempt fails and he reconsiders.
Anna jumps and dies under a train after everything falls apart for her. Vronsky did love her till the end, but their life felt unsatisfying for Anna because she was too much of an outcast for a really long time.
Simone most of the way through Idlewild. Depression results from the many revelations of the plot, and escape is all too easy.
In Dust And Shadow, the soldier that Sherlock Holmes initially suspected of being Jack the Ripper kills himself over the shame of having stabbed the (disputed) first victim, Martha Tabram, in an angry passion. He did not kill her, though no one but Holmes would have (and did) worked that one out.
In Veniss Underground, Nicholas is turned into a repulsive monster by Quin as a karmic punishment for his sins. He chooses to leap to his death rather than continue to live in his hideous new shape.
In Vampire Academy, shadow-kissed Anna, the guardian and companion to Saint Vladimir, grew unstable following his death and committed suicide.
In Six-Gun Snow White, Gun That Sings tried to cut her wrists after finding out she was pregnant.
Shai in The Emperor's Soul has five Essence Marks (powerful magical items capable of rewriting a person's history). Four simply grant new skills and some physical changes, but let her remember who and what she is. But the fifth, if ever used, would totally erase her old life. As far as she would then know, the simple farm-girl life that Mark gives her would be the only life she'd ever had. She has no plans to use it, but just the fact that she made the thing (Essence Marks take years of dedicated labor to make) is a bit disturbing.
In the Spiral Arm series, there are are a couple of examples during the civil war in the Lion's Mouth. Shadow Prime, the mentor of all Shadows, is driven to despair and eventually death by the sight of his students divided and slaughtering one another; and Kelly Stapellaufer, whose infidelity provided a pretext for the beginning of the civil war, kills both her lovers and then herself.
Since the majority of Half World takes place in the eponymous purgatory, this is a given. There are people in Half World caught in an endless loop, repeating their suicides over and over again. Suberted with Ms. Wei, who contemplated suicide but ultimately decided not to, but played straight with a character in Darkest Light.
In Midnight's Children, Saleem's uncle Hanif jumps off a building after Homi Catrack — his sole source of income — is murdered. Saleem blames himself, as he initiated the chain of events that led to Homi's murder.
The Calvarians are prone to this due to their being a Proud Warrior Race, who would rather die than live with the shame of failure. In The Baron of Maleperduys, over half of the Calvarian survivors of a battle that ended in defeat request permission to fall on their own swords. Their commanding officer turns them all down, but only because he can't afford to lose any more soldiers.
Moire, the second mate of the Quicksilver, succumbs to this in Reynard the Fox when it dawns on her that she is pregnant with at least one Chimera child after having been subjected to a horrifying sexual assault at their hands.
Randy Morrison in Star Trek The Eugenics Wars, who was already paranoid and a little unhinged, goes completely insane when Roberta foils his terrorist plot. Convinced that (imaginary) black NWO helicopters are coming to claim him for a show trial, he vaporizes himself with Robertas servo.
In Divergent, Peter somehow convinces Al to help out in a plot to kill Tris. He feels guilty afterwards, and when she refuses to forgive him Al throws himself into the chasm and takes his own life.
Averted in The Hunger Games series, but not for want of attempting. Katniss understandably attempts various suicidal things after the end of the war in the final book. None are successful naturally, although the fact she narrates the books isn't in itself a giveaway since the books are in present, rather than past tense.
The title character in Eden Green becomes infected with a horrible needle symbiote that keeps her alive no matter what; most of the book chronicles her attempts to find a way to end her own life.
In Room, after an interview leads her to believe that she failed to do what was best for her beloved son, Jack, by not getting him out of the titular room they were held prisoner in for 5+ years, Ma attempts to overdose on pills.
In Requiem, Madgie felt so much regret about her time travel experiment that, before they could reverse it, she jumps into a ravine, dying shortly after impact.
She does it again in Memories to keep from losing her memories, the things that she would have lost as what little sanity she had possessed would unlikely have withstood the great amnesia.
This has happened Toki so many times, once in Insanity and Resentment and, before that, possibly, she tried to get herself runover by a car in Flashbacks I (no one knows her real motives and Toki may never tell them, though, she could have been leaving to die in peace but, at that point, getting runover with a car would most certainly prove fatal). Both are understandable because, in the first one, she is mentally ill Hmm? Toki has multiple mental illnesses, one of which is schizophrenia and, for those who don't know, schizophrenics have been known to attempt suicide more than once. and, the latter, is because she is really sick with leukemia and was being abused and neglected at the time (in conjunctions with the fact that she in the later stages and is virtually dying). Neither has anything to do with her heritage.
Deconstructed to a decent extent with her motives in the poem A Plea to River Seine, in that they are very well thought out and were pulled apart from what they are.