This is a common theme throughout the novels of Jane Austen, of the heroine being torn between a dependable, caring man and a libertinish cad. She will always choose the former, but Austen will keep you guessing as to who it is. (The exception is Lady Susan, as she is an anti-heroine who is herself a Veronica.)
Pride and Prejudice: With Elizabeth, Darcy is the Betty and Wickham is the Veronica, although it appears to be the other way around at first.
Mansfield Park: With Fanny, Edmund is the Betty and Henry is the Veronica; with Edmund, Fanny is the Betty and Mary is the Veronica; with Henry Crawford, Fanny is the Betty and Maria is the Veronica; with Maria Bertram, Rushworth is the Betty and Henry is the Veronica.
Emma: With Emma, George Knightley is the Betty and Frank Churchill is the Veronica.
The first is Hermione choosing between the famous, popular, mysterious and intense Viktor Krum (Veronica) and her good friend Ron (Betty). (Though personality-wise, Krum was a Nice Guy who would have been a nice Betty if given the chance)
This trope is played with canonically on the Lily/Snape/James triangle. Snape's Pensieved memories show that Snape (who was in love with Lily all along) was originally Lily's best friend, while she wanted nothing to do with arrogant bully James. This changes and Lily eventually marries James, but interestingly it seems that this only happens once Snape switches to the Veronica (by insulting Lily and calling her "mudblood") while James becomes the Betty (by acting less arrogant and more mature once he left school). It's like a Betty and Veronica love triangle where Archie has no interest in the Veronica... whoever it may be at a given time.J. K. Rowling has expressed her dismay with the fact that All Girls Want Bad Boys in interviews, so this may simply be Lily defying that trope in combination with an Hourglass Plot.
Ron caught between his long time friend Hermione and the "fangirl" Lavender Brown.
Harry goes from Cho Chang, the "very pretty" popular girl with long dark hair, to his team-mate and best friend's little sister Ginny.
In Charles Dickens' David Copperfield, the titular character initially marries the charmingly ditzy Dora Spenlow (Veronica), and only later discovers and returns the love of the gentle, supportive Agnes Wickfield (Betty).
This is the case about the triangle between Piper, Reyna, and Jason; however, it is unclear as to who is considered who, since both girls could be justified as either the Betty or the Veronica. Piper could be the Betty, since she is nicer, more outgoing, and less confident than the stoic Reyna (she believes that Reyna is more beautiful that her) and she just wants Jason to be happy no matter who he is with; she could also be the Veronica, since she is considered more beautiful than Reyna by Jason and she unintentionally interferes in what might have became a romance between the amnesiac Jason and Reyna. In the same way, Reyna could be the Betty, since she and Jason have known each other longer because she and Jason were best friends when he was at Camp Jupiter and she held romantic feelings for him (which were unrequited by Jason, he admits so himself), or she could be the Veronica, since she is meaner, more confident, and more aggressive (more "Roman") than the homely Piper and hides any feelings she has for Jason but wants him for herself. Ultimately, Jason chooses Piper, since he loves her for being who she is, and he never had any feelings for Reyna.
Subverted with Leo, Frank, and Hazel, since Leo doesn't act on any feelings he has for Hazel, and Hazel isn't in love with Leo but rather with Frank. However, who is the Betty and who is the Veronica is more clear cut in this case. Frank is the Betty, since he and Hazel are best friends, he houses feelings for her, and he lacks self-confidence, while Leo is the Veronica, since he interferes in and complicates Hazel and Frank's relationship and is far more assured of himself than Frank is. By The House of Hades, this triangle is effectively over, since Leo has fallen in love with Calypso.. All three of the characters comment on this new development.
Piers Anthony's Isle of View (say it out loud) in the Xanth series resolves the Betty and Veronica love triangle between Prince Dolph and his two fiancees: Electra (sweet, willing, but unexciting) and Nada Naga (exotic, beautiful, but uninterested). By the time it's resolved a few books later, all three characters have been sufficiently Flanderized that there's no reason to care anymore.
In R. Scott Bakker's Second Apocalypse the blonde, brainless, surprisingly-innocent Serwe is Betty and the dark-haired, intelligent prostitute Esmenet is Veronica.
Victor Hugo's Les Misérables and all of its kajillion adaptations do this. The rebellious student Marius (Archie), the cultured and mysterious orphan Cosette (Betty), and the spunky, determined, and quite possibly not-right-in-the-head street urchin Eponine (Veronica), the winner being Cosette. However, this was inevitable due to Values Dissonance. Eponine was intended as a living critique of 19th century France's rigid class system: she never could get in a relationship with the (broke, but still) aristocratic Marius, because they just weren't considered equals.
And then there's Hugo's other classic, The Hunchback of Notre Dame, with Phoebus engaged to undeniably good-looking and marriageable fiance, Fleur-de-Lys (Betty) (a "white-skinned beauty"), but lusting after the disturbingly beautiful golden-skinned, black-haired gypsy Esmeralda (Veronica), who he would never marry, let alone be seen with. Fleur-de-Lys and Esmeralda fit the traditional physical descriptions and relationship standings of Betty and Veronica, respectively, but Esmeralda is a much nicer person and destined to lose, diverting from the Veronica's usual icy behavior and unattainability.
The Man Who Laughs, where Gwynplaine is torn between the extremely sweet Dea and the rather perverted Duchess Josiana.
Stardust: Tristran has to make a Red Pill, Blue Pill choice between the magical shooting star Yvaine (Betty) and his former crush Victoria (Veronica). Yvaine wins.
Although you can argue that Victoria is actually the Betty (being the one Tristran was originally in love with and a normal human) and Yvaine the Veronica (being the magical, more 'exotic' choice and a bit of a Defrosting Ice Queen). It's a bait and switch of this trope, really.
In Stephanie Meyer's Twilight saga, gender roles are switched—the protagonist, Bella Swan, has to choose between Edward and Jacob. Interestingly, which is the "Betty" and which is the "Veronica" depends on the reader: "Team Edward" readers see Edward as the Romantic Vampire Boy who's a Misunderstood Loner with a Heart of Gold while Jacob is a Manipulative Bastard who forces himself on her, once even emotionally blackmailing her into kissing him. "Team Jacob" readers, on the other hand, see Jacob as the Dogged Nice Guy who's always been there for her as her Childhood Friend, while Edward is a Stalker with a Crush turned Crazy Jealous Guy, even going so far as to remove part of her car's engine to keep her from visiting Jacob. Technically, Edward and Jacob are both Veronicas in terms of danger, since it's demonstrated many times throughout the series that both vampires and werewolves are always in danger of harming their human significant others. The only true Betty in the series is Mike Newton, and he was never really in the running anyway.
Oksa Pollock has also a gender-flipped version with two Bettys: Oksa has to choose between Tugdual (Veronica), her childhood-friend Gus (Betty) and Merlin (a friend from her school in London, also a Betty)
In L. J. Smith's Vampire Diaries, Elena (Archie) has to choose between her true soulmate, Stefan (Betty) and her wild, dangerous companion, Damon (Veronica). Elena ends up choosing Stefan as her final choice. There are other triangles that have existed in the novels, with Stefan being involved in the vast majority of them. There's also Katherine (Archie) / Stefan (Betty) / Damon (Veronica)
Honor Harrington gives an interesting example in which not the hero, but a supporting character, Hamish Alexander, gets torn between his beautiful, loving and brilliant, but invalid wife, Emily (the Betty), and lively, athletic and no less beautiful protege and subordinate, titular Honor Harrington. Being an Officer and a Gentleman, Hamish decided to simply suffer nobly in silence, which brought a truly monumental number of problems for at least three books until he was whacked on the head by none other than his own wife. He then went on to marry both, neatly solving the issue.
Bridget Jones's Diary plays this fairly straight between Mark Darcy (Betty) and Daniel Cleaver (Veronica). The film version even describes them as "too good to be true" and "so wrong he might just be right", respectively. By the end of the first two books, Mark has won, although when Helen Fielding continued the column, apparently Bridget was still torn between them and ends up having Daniel's baby. Sigh.
Kushiel's Legacy has Imriel torn between his dutiful love for gentle brunette wife Dorelei, and his socially inappropriate and fairly kinky attachment to glamorous, feisty blonde heiress Sidonie, a Defrosting Ice Queen.
In the Russian version of the tale The Shadow, written by E. Shwartz, the scientist Christian Theodore, after defeating his shadow, chooses to marry the faithful Annunciata, rather than the shallow (as it turns out) princess, his previous love interest.
Very early example: the eponymous hero of Daniel Deronda has to choose between sweet, emotionally fragile Jewish musician Mirah and shallow, socialite-fallen-on-hard-times Gwendolen. In a very unpopular move for the times, he chooses Mirah. It was so unpopular, in fact, that an American novelist actually wrote a "sequel," Gwendolen, in which Deronda reconverts to Christianity and marries Gwendolen!
Tipping the Velvet: In a rare lesbian example, Nan has to decide between her beautiful, faithless, music hall artiste ex Kitty and her feisty socialist girlfriend Florence. She chooses Flo. Partly ruined by the TV adaptation, which insists on turning the savvy Flo into an innocent wet weakling. It might be this change in focus that led many fans to complain she should have picked Kitty.
In Gottfried Keller's Green Henry (1854/55) the protagonist is torn between the sweet Anna and the passionate Judith.
In the novel as well as the film Starter for 10, Brian Jackson is faced with a similar dilemma - he is heavily attracted to his sexy University Challenge teammate Alice (the somewhat 'slutty' Veronica) but somewhat attracted to intuitive activist Rebecca (a more forceful Betty who isn't the 'girl-next-door'), whom he doesn't realize he's better off with. He does realize he's better off with Rebecca and 'breaks up' with Alice (after she slept with his best friend).
In the Stephanie Plum series, the protagonist of the same name is caught in a love triangle between her childhood friend Joe Morelli and the more mysterious Ranger. However, Joe Morelli isn't exactly your run-of-the-mill goody-two-shoes Betty.
In the Dragonlance novels, red headed Tanis Half-Elven has to choose between Laurana, a sweet, innocent blonde elven princess, and Kitiara, a sultry brunette human warlord. After a great deal of indecision and whining about how horrible it is to have two gorgeous women in love with him, Tanis finally chooses Laurana, mainly because he feels responsible when Kitiara tries to resolve the triangle by kidnapping Laurana and attempting to have her killed.
In The Age of Innocence, Newland Archer is engaged to the blond, blue-eyed, "perfect" - and completely superficial and ordinary - May Welland (the Betty), but falls in love with her dark-haired cousin Ellen, the family reprobate (the Veronica). Interestingly, the trope is somewhat inverted, as in this case, it's The Veronica who is more suited to him in terms of personality and interests.
In Everwild, Allie finds herself in a love triangle with Mikey (Betty) and Milos (Veronica).
Though at the time, Allie might have seen Mikey as the Veronica and Milos as the Betty, based on their attitudes.
In The Night Angel Trilogy, Kylar finds that he has feelings for the pure and well-meaning Elene (Betty), but also finds himself drawn to the violent and fiery Vi (Veronica) as well. In the end Elene sacrifices herself, leaving Vi and Kylar for each other...
Played straight in Stephen Donaldson's The Mirror of Her Dreams, with Terisa, who has to choose between Geraden (Betty) and Eremis (Veronica). Geraden wins, since Eremis is evil and has been trying to kill Terisa and Geraden for most of the book. For added Squick, his intentions seemed to be to sleep with her, and then kill her.
Girl with a Pearl Earring by Tracey Chevalier has a gender-flipped example: Pieter the son as Betty and Vermeer as Veronica, with Griet as the Archie.
Moonlight - which can be fairly described as "Twilight with werewolves" - plays this straight, but with a twist. Kayla, the heroine, identifies Lucas as the Bad Boy, and Mason as the "safe" guy. The twist is, even before Mason's Face–Heel Turn, reading between the lines reveals that she's got it backwards. Lucas is gruff, aloof, and has an animal magnetism that terrifies her, but he also protects her, trusts her, and never forces her to do anything she's unable to cope with. Mason, while charming and intelligent, comes on to her rather insistently, acts possessive, demonstrates overt disrespect for Lucas (who more or less ignores him in return), and - most tellingly - uses beer smuggled on the trip to get Kayla buzzed before a night of stargazing.
In Barefoot Boy with Cheek by Max Shulman, Asa Hearthrug spends a chapter unable to decide between the patrician Noblesse Oblige and campus communist Yetta Samovar.
Subverted somewhat disturbingly in The Lover by AB Yehoshua, with the quiet day-in-day-out Adam intentionally fixing up his wife with young artist Gabriel as a lover, and later doing it with his daughter’s friend Tali.
In Dostoevsky'sThe Idiot, Prince Myshkin is forced to choose between Aglaia, a girl with a good reputation from a respectable household, and the scandalous, self-destructive Nastassya Filippovna. He chooses...poorly. Somewhat subverted in that Aglaia is very much a Tsundere which makes her pretty far from the typical Betty prototype.
Some V. C. Andrews' books gender-flip this trope. And yes, one of the suitors will turn out to be blood-related to the heroine. No exceptions.
Played straight in The Wheel of Time with Lews Therin Telamon's two love interests: the ambitious, dark-haired, dark-eyed channeler Mierin Eronaile, and the red-gold-haired Ilyena Moerelle Dalisar, who has no powers to speak of. He chooses Ilyena, then goes mad and kills her. Mierin's jealousy of Ilyena might have played a role in her decision to become Lanfear, the first of the Forsaken.
In Drums, Girls, and Dangerous Pie, the hero Steven must choose between Annette Watson (Betty) and Renee Albert (Veronica). He chooses Annette.
In Boris Vian's ''L'écume des jours'', the two women in the hero's life, bold sexy Alise and delicate Chloé, are reasonable matches for Veronica and Betty respectively. However, there's no real competition between them because Alise chooses someone else early on in the story.
Matched by Ally Condie is about a dystopian society where everything you do, including your future spouse, is determined by statistics on you and your age group. Cassia has her "matching" ceremony where she is matched with her close childhood friend, Xander. However, the next day she sees that she is matched with Ky. She now must choose between Xander, the person society chose for her, and Ky, a rebellious "Aberration" who should not have beeen matched in the first place.
Discussed in Faking It by Jennifer Crusie about choosing between the muffin (Betty) and the doughnut (Veronica). The doughnut is exciting and fun and gorgeous, whereas the muffin just kinds of sit there, "lumpy, looking alike, no chocolate frosting." But while the doughnut is good for a one night stand, its sticky and no longer crispy the next morning. Muffins, however, taste better the next day, and are there for the long haul.
Played with in Girl in Translation by Jean Kwok. Curt is the Betty, because he is probably the safest option for her especially after she gets pregnant. Curt is very wealthy and has a high status in her school. Matt could be either Betty or Veronica, depending on your point of view. Matt could be Betty because he is the one she's always wanted, her mother knows him, and he is also Chinese. He could be the Veronica because he is poor and for some parts of the book already has another girlfriend. In the end, Kimberly chooses neither. Matt marries his girlfriend, but Kimberly and him do share a kiss.
Sisterhood Series by Fern Michaels: Deconstructed in the book Sweet Revenge! The book has Bobby Harcourt (Archie), Isabelle Flanders (Betty), and Rosemary Hershey (Veronica). Bobby and Isabelle were going to be married. However, Rosemary hated Isabelle's guts and had her framed for drunk driving that resulted in the deaths of three people. Isabelle ends up being ruined and loses everything. Bobby, in a Moment of Weakness (and lust) ends up having sex with Rosemary and marries her instead. By the book Sweet Revenge, however, things change. Bobby ends up realizing that Rosemary is a Jerkass with an It's All About Me attitude and decides to divorce her. Isabelle ends up back in a position of prominence and works hard to ruin Rosemary. Rosemary goes Ax-Crazy, ends up losing everything, gets ruined, and is last seen placed in a mental institution, possibly to never become lucid again. Isabelle and Bobby did have a short dialogue, but it is painfully clear that it is too late for both of them to have the sort of relationship they once had. So Bobby, thanks to his foolishness, ends up with nothing in a sense, and is forced to realize that he wasted years of his life with the wrong woman.
In The Hunger Games, Gale and Peeta both possess some Betty and some Veronica traits in their love triangle with Katniss. Personality wise, Peeta is the Betty (meek, kind and had a crush on Katniss since they were young) while Gale as the Veronica (dark-haired, handsome and more "dangerous"). However, role-wise, Gale is the Betty, as he's Katniss's old friend and partner, and probably is the one she would've ended up marrying if the books had never happened. Meanwhile, Peeta is the other choice, and one she's afraid to make.
Ivanhoe was fought over between Rowena and Rebecca. Temperament wise, moody Rowena is the Veronica while kind Rebecca is the Betty. Situation wise, aristocratic Rowena is the safe choice (Betty), and exotic Rebecca is the riskier one (Veronica). Ivanhoe was already in love with Rowena from before Rebecca came into the picture, so yeah.
Rich, blond Edgar being the Betty; dark, poor, dangerous Heathcliff playing the Veronica; and selfish Catherine as the Archie. She "picks" Edgar by marrying him, but her heart always belongs to Heathcliff.
It happens in the second generation; Linton is the meek, sickly Betty, and the childhood friend of the energetic Cathy, while Hareton is the gruff, sour, and moody Veronica. Though funnily enough they're both Boys Next Door. She picks Hareton, but after it turns out that Linton has a Veronica streak himself—namely being a cowardly Control Freak who guilt-trips her into an abusive marriage with him. And then it turns out that Hareton is pretty nice, he just has No Social Skills.
The narrator of Richard Powell's Don Quixote, U.S.A. intended to remain true to his blonde girlfriend Sally (Betty), a photographer for Life, only to be increasingly attracted to the fiery brunette Conchita (Veronica), member of a South American rebel group and well-practiced user of a "burp gun."
In Kazuo Ishiguro's Never Let Me Go, and the film it inspired, Kathy is Betty and Ruth is Veronica to Tommy.
In I Can Get It for You Wholesale by Jerome Weidman, Harry Bogen's love interests are his childhood neighbor's daughter Ruthie Rivkin (whose friends call her "Betty", though the name doesn't stick with him) and hard-to-get actress Martha Mills. In the book he clearly prefers the Shiksa Goddess to Ruthie, whom he considers too Jewish-looking for his ambitions even if his mother approves of her; in the musical version he does ultimately end up with Ruthie.
In Vikram Seth's novel An Equal Music, Julia has the calm grounded James, and the moody Anti-Hero (and narrator) Michael.
Although mostly not in direct competition thanks to a case of That Man Is Dead, in The Fallen Moon Flell and Skade are in a type of Betty and Veronica relationship with Arren/Arenadd. Flell (Betty) is a nice, gentle, wellborn griffiner who loves Arren despite her society's prejudice against Northerners. Skade (Veronica) is an exiled and shapechanged griffin with her species more aggressive traits, but becomes loyal to and dependent on Arenadd.
Subverted in The Host. Ian and Jared fit the bill all right, the subversion being that the Archie is actually two people in the same body with Ian only interested in Wanda and Jared interested in Melanie. Honestly, it could be viewed as a metaphor for a guy loving you for you for your mind/personality vs. a guy loving you for your body.
In Looking for Alaska, Miles Halter (a.k.a. "Pudge")has to choose between Lara Buterskaya - a relatively "normal" Romanian immigrant and his girlfriend, and the titular Alaska Young - a "wild, self-destructive, moody, unpredictable, beautiful and enigmatic girl who captures Pudge's attention and heart."
In Poul Anderson's "Flight to Forever", Eva, sweet and gentle, is Betty and Taury, the rightful Galactic Empress is Veronica. However, they are not in direct conflict; Martin is traveling through time, only able to go forward, and it is the memory of Eva, to whom he can never return, that he has to wrestle with before he accepts she's gone. At the end, when he's forced to leave Taury, god-like beings direct him to the end of the universe so that he cycles back to Eva, and then destroy the machine; he reminds himself that while Eva is not Taury, she has her own charms.
In Wolf Captured of Jane Lindskold's Firekeeper series, Firekeeper finds herself in a particularly exotic variant. Not only is she pursued by two males, but both her Betty AND her Veronica are a pair of exceptionally large and sapient wolves. And this is after she finds herself the Betty to a female wolf for the attentions of her own Betty. The happy secondary ending comes for both Veronicas when the female wolf claims the male challenger for herself, while accepting Firekeeper as the pack's One Female, or alpha female.
In-universe example in "Author! Author!" by Isaac Asimov. In the protagonist's latest unpublished book, his series detective Reginald De Meister has two love interests: Letitia Reynolds is the Betty, Sancha Rodriguez is the Veronica who dies in Chapter Six. At least, that's the state of play when the story opens.
In Tolstoi’s Resurrection, Prince Dmitri is sort of engaged to respectable fellow noble Missy but guilt leads him back to the servant he seduced, Katyusha, now a prostitute on trial for murdering a client.
Bluefur had Thrushpelt as her Betty and Oakheart as her Veronica; to further emphasize this, everyone in her Clan ships her with Thrushpelt (which actually bothers her a bit, since she doesn't want to feel forced into a relationship), while Oakheart is from a different Clan. In an unusual twist, she chose Oakheart, but had to cover up the kits from their affair by "choosing" Thrushpelt.
His daughter, Squirrelflight, has the popular and hard-working Ashfur as her Betty and the ambitious and loner-ish Brambleclaw as her Veronica, helped by the fact that Brambleclaw is the son of her father's mortal enemy. It turns out, however, that Ashfur is much more Veronica than Brambleclaw could ever be—when Squirrelflight picks Brambleclaw over him, he tries to murder her father and kits in revenge.
Brambleclaw (or rather, Bramblestar) himself later gets to choose between Squirrelflight, acting as Betty since she's matured into a reliable, level-headed warrior, and Jessy, acting as Veronica since she's an abrasive kittypet he rescued from drowning. He chooses Squirrelflight, though according to Word of God there was never really a triangle, because he would always choose her.
Dovewing's got the eager-to-please, kind-hearted Bumblestripe as her Betty and the more mysterious Tigerheart as her Veronica. She picked Bumblestripe, but later broke up with Bumblestripe because she still had feelings for Tigerheart. Thus, in a way, she chose neither.
Deltora Quest has the genderflipped version with the straightlaced, dependable Lief (Betty) and the exotic-but-beautiful Dain (Veronica) for Jasmine's Archie.
In "De skandalösa" by Simona Ahrnstedt, Magdalena Swärd is torn between two men. She sees Peter Cronstedt as the boring but safe choice (the Betty), and even though he once betrayed her, she wonders if she shouldn't forgive him. By contrast, she sees Gabriel Gripklo as the exciting but dangerous choice (the Veronica), but since he's a high-ranked aristrocrat, she could never have an equal relationship with him. But it turns out that Peter really is a jerk, and Gabriel is willing to marry her after all.
Gabriel has to make a similar choice between fellow aristocrat Venus Dag och Natt, who would be his mother's choice to be his bride (the Betty), and Magdalena, who is more interesting to him even though she is a penniless orphan with no powerful relatives (the Veronica). He will choose Magdalena in the end.
Poul Anderson plays it Up to Eleven in Sargasso of Lost Starships. Helena is an attractive woman and an efficient and disciplined military officer, whose dreams of romance include marrying Basil and working with him to help his planet integrate with the empire; Basil's Old Retainer approves because she will give him good sons. Velduma is an alien of enormous powers, who appears to Basil as one of The Beautiful Elite, and is also sadistic and completely mad.
Young and inexperienced Andie may seem like the Betty to Nick's Archie, while sexy cunning Amy may seem like the Veronica. But the truth is, Amy is Nick's wife, while Andie is his 20 year old mistress. That, and the film version makes Andie seem even more forward in her initiating sex with Nick.
Clean-cut millionaire Desi who comes to Amy's rescue may seem like a Betty at first, but one needs to remember that he stalked Amy in the past- not to mention does not treat her all that well when she stays at the lake house. Nick may seem like a Veronica in that he was a sociopath who eventually cheated- but he also was nowhere near as rich and alluring as Desi.
For Fausto Mirra in the Ahriman Trilogy, exciting, tattooed badass Zoe Durant is the Veronica, while normal, boring Ashley is the Betty. Zoe is also Simon's Veronica, but kind, bespectacled Erin is his Betty.
Rose between Mason (Betty) and Dimitri (Veronica). Mason is a close childhood friend, who adores her, and offers her a safe relationship. Dimitri is her older mentor and their relationship is forbidden. Later it's Rose between Dimitri and Adrian, though which one is the Betty or Veronica depends on the situation (usually Dimitri is the Betty but when he's a Strigoi he is definitely a Veronica). Dimitri is more down-to-earth while Adrian is wealthy, glamorous, and likes to show-off. During Dimitri's Strigoi phase, Adrian offers a safer relationship to Rose and proves devoted, while Dimitri is dangerous and is willing to completely dominate his lover.
Lissa between Aaron (Betty) and Christian (Veronica) in the first book. Aaron is her former boyfriend, first love, and is still crazy about her. But he is boring. While Christian is a fascinating bad boy with an edge.
Poul Anderson's Corridors of Time. Storm, at first a mysterious and wealthy woman who pays for Lockridge's lawyer and for private detectives to find the evidence to clear him, soon reveals that she is a time-traveler and a leader of her society; always a stunning beauty. A rather nasty society, he later learns. Auri is a simple and good-hearted girl from Neolithic Scandanavia.
REAL has two subversions of the trope. Since most of the story takes place in the titular Metaverse, things get complicated:
It initially appears to be the case between Neru's teammate Betti (Betty) and Likaï (Veronica), as the former openly hits on Neru, who is oblivious and feels drawn to Likaï. It gets subverted very quickly: Likaï betrays Neru's trust, and it turns out that Betti was only after the glory of being Neru's girlfriend after he joined the Pantheon - she dumps him as soon as his account gets stolen.
The story moves on to a similar dynamic between Neru, Fasia (Betty) and Likaï (Veronica), who are both variations of the Manic Pixie Dream Girl: Neru befriended Likaï in The Metaverse but doesn't even know their gender, and Fasia is a complete stranger he meets in the real world who decides to help him out when no one else would. It is also subverted: [[spoiler: the physical attraction Neru feels towards Fasia is merely that: physical. It doesn't last, and is one-sided from the get-go. In the end Neru fully embraces the fact that he was only ever interested romantically in Likaï, and the latter's Gender Revealdoesn't change anything.
The Pearl and the Carnelian: On one hand, Hester, the protagonist's lover, is a gentle, kind-hearted girl (Betty), while Eugen von Frenzel is a charismatic foreigner with VERY questionable ideals. On the other hand, though, this being 1930s, romance with Hester is more dangerous for Lucy.
There is a more straight-up example for Hester herself: cheerful housemaid Abigail vs. gorgeous Nazi Noblewoman Lucy.
Firstly, Larry meets Nadine Cross (Veronica), the enigmatic woman who he longs for, and who at first refuses his advances and who has up to this point been holding out for the Dark Man. He then meets Lucy Swann (Betty), a bit of a Dumb Blonde, who is... significantly less reserved in that regard.
The genderflipped version occurs for Nadine with Larry (Betty) and Randall Flagg (Veronica), who she's dreamed about since her youth. She at first rejects Larry, but then tries to have him, after he's already chosen Lucy. This pushes her into Flagg's arms.
Many romance novels by Iny Lorentz invoke this trope for the heroine, with the male Betty usually being a childhood friend and the ultimately lucky one.
In Die Pilgerin, Tilla has a thing for Chivalrous Pervert Aymer de Saltilieu (the "chivalrous" part being less obvious), and while she never ceases to be attracted to him she also marries her childhood friend Sebastian.
In Dezembersturm, however, there is the reverse since the Nice Guy who has supported the heroine Laura throughout the novel is revealed to be married and without any feelings but friendship towards Laura, and she marries the more roguish and wild Fridolin.
In the beginning of The Sorcerers Daughter, there are the nice and cheerful if reckless Siegfried (Betty) and the bitter and brooding if clever and very attractive Rothbart (Veronica) for Odette. Later on, as Siegfried becomes more serious and Rothbart warms up, the contrast blurs a little, but essentially remains. Rothbart wins.
In Into The Hinterlands by David Drake and John Lambshead, Allen Allenson's two love interests, Lady Trina Blaisdel and Sarai Destry have this comparison. Trina is a sweet, friendly society widow with a couple children, Sarai is a Man-Eater married to his friend Destry for political reasons. Allenson has an affair with Sarai for much of the first book but knows she's bad for him, whereas Trina puts him at ease and is extremely helpful to him but doesn't arouse his passions. He ultimately asks Trina to marry him at the end of the book.