In The Count of Monte Cristo, envy is the motivating force of two of the conspirators — Danglars is jealous of Dantes' success, and Fernand of his fiancée.
Inga in All Stays In The Family is jealous of Dora and Olaf's (her love) obvious infatuation. She can't hide it anyhow and it's strong enough that Dora starts suspecting Inga was one of she-werewolves who attacked her earlier. Even after she finds out that "obvious infatuation" was an act to draw out the attackers, Inga still doesn't trust Dora.
Demandred in The Wheel of Time became evil because he envied the fact that Lews Therin was slightly better than him in every way. Also, Lanfear envied Ilyena for marrying Lews Therin. The same applies to Sammael, who was as skilled a general and sportsman as Lew Therin but felt that his height was the reason he was the less honored of the two. Be'lal (one of whose nicknames is "The Envious" was reputedly extremely jealous of virtually everyone; Lews Therin, Lanfear and Ishamael amongst them. A case could be made this was true of a lot of the Forsaken, many of whom were prominent Light side generals or otherwise decent figures but jealous of the acclaim given to the chosen leader Lews Therin or perceived general lack of acclaim for themselves. Not all though. Semirhage in particular may have been the greatest healer in the world but she was also a vicious sadist long before the Dark One appeared, and Ishamael, as Elan Morin Tedroni, seems to have switched sides for philosophical reasons.
In Dan Abnett's Gaunt's Ghosts novel Ghostmaker, Inquisitor Lilith actively tries to foment this between Gaunt and Corbec. Gaunt slaps her down because he realizes she's doing it, and she doesn't need to, when he is willing to work with her. She apologizes, saying she is too used to having to manipulate people to get the to do what is needed (although at the end, she reveals that she had actually found Gaunt attractive).
In Deus Sanguinius, Inquisitor Stele plays on Rafen's fears of envying him to convince him that he ought to die to free Arkio; Rafen has a desperate time breaking free, receiving assistance toward it. Later, when Arkio believes that he has killed Rafen, he feels a freedom he had coveted a long time.
In Alexander Pushkin's Mozart and Salieri, Saliery explains how he hates Mozart for being so talented while never having to strain where he, who dedicated his entire life to music, lacks such talent. This is definitely a Historical Villain Upgrade.
In C. S. Lewis' Till We Have Faces, a retelling of Psyche and Cupid, Orual hears that she persuaded Psyche to bring in the lamp at night and so lose him, because she was jealous. Infuriated by this injustice, she writes her story to make the truth known. Writing it, and the events afterwards, reveal to her that she was jealous: having raised Psyche from childhood, she was jealous of Cupid.
In The Voyage of the Dawn Treader, one temptation for Lucy to cast the spell to make her beautiful was that it would make Susan, always the beauty of the family, jealous of her.
In Jim Butcher's The Dresden Files novel Turn Coat, we learn that in the Back StoryMorgan was in love with Luccio and so became jealous of Harry. In fact, Luccio was afraid he had hunted Harry down out of it. Then Morgan dies. And Luccio learns that she had been magically manipulated to "love" Harry.
In Graham McNeill's Warhammer 40,000Ultramarines novel Courage and Honour, Uriel is warned of Leachrus, who had commanded his company in his absence. Later, he has it out with him: when Leachrus claims not to resent him, Uriel accuses of him of lying, and Leachrus reluctantly admits that he wants Uriel's post, and with Uriel gone so long, he had gotten used to it. Uriel agrees that his ambition is not wrong and predicts that he will get a captaincy, one day.
In The Chessman of Mars, O-Tar is jealous of his son A-Kor because A-Kor would be much better for the throne than O-Tar is, and everyone knows it.
Dragonlance: Raistlin is very jealous of his brother's looks, charm, health, strength and popularity.
Likewise Kitiara is incredibly jealous of her romantic rival Laurana's impossible beauty. This jealousy causes Kit to relentlessly stalk Laurana and attempt to kill her rival. Even after Kitiara defeats Laurana and has the elfmaid as a prisoner completely at her mercy, she still can't let it go and continues to obsess about how Laurana is more beautiful than her.
In Wen Spencer's Endless Blue, Mikhail feels deeply guilty that (in the Back Story) in his jealousy that Turk did not have to attend formal functions and got a trainer rather than a tutor, he did not consider what the trainer did until he accidentally stumbled on the Cold-Blooded Torture that was training for Reds. He put a stop to it at once, but thinks he should have thought earlier. Hardin reveals that he was jealous of Mikhail, because his Royal Blood ensured that he would be, at least, a footnote in history, and deliberately sabotuged his career because of it.
Harry also experiences this when he sees Ginny kissing Dean. It's described as a roaring monster in his chest.
Arguably the series' biggest example was Severus Snape. He had a famous and bitter hate of James, who reciprocated it. While James' reasons aren't given explicitly given (though it was said he despied the Dark Arts and Snape was a natural at it), but Snape was envious of James' life compared to his (James was well-off, talented at Quidditch, intelligent, good-looking and a pretty nice guy, albeit prideful). This got worse when he discovered James liked Lily Evans (his only friend and also one-sided romantic interest). He never got over this as an adult and in fact, passed the hate down to James' son, Harry.
Ivypool from Warrior Cats has this towards Dovewing because of her powers. But this is only because she doesn't know of her powers yet, and she gets really tired of living as her sister's "echo." However, she overcomes her jealosy when Dovewing reveals her powers after hearing Tigerstar's plan.
Foxheart in regards to Yellowfang liking Raggedstar, thus making the former's life hell for her.
Kludd from Guardians of Ga'Hoole feels jealousy towards Soren because he thinks his litte brother gets more attention. He doesn't get better, though.
Each of the villains in the Keys to the Kingdom series represents a deadly sin, with Superior Saturday representing envy. She has become absolutely consumed by the fact that Lord Sunday controls the Incomparable Gardens (the epicenter of the universe), and she does not. She spends ten thousand years attempting to correct this fact through the following means:
Turning her demesne into an immense tower to try to breach the underside of the Gardens.
Attempting to destroy the four Drasil trees which are forever growing and taking the Gardens out of reach.
In her titular book, she succeeds by sinking two sevenths of the House into nothing, an action of such catastrophic affect that by one of the last chapters of the book, nearly all of the House has been consumed.
Attempting to assassinate various figures of power.
Attempting to remove Arthur, the protagonist and rightful heir to her demesne and Lord Sunday's, from power via various means.
Betraying one of her closer friends and turning her into a Leviathan rather than letting her give power to Arthur or another heir.
and inflicting amnesia upon the Piper's Children because of a prophecy that states that doing so will prevent Arthur from winning.
In short, she would be the Big Bad if it weren't for the fact that Lord Sunday was so much more powerful than she.
Ella Enchanted: Hattie is jealous of Ella because she's brave, smart, and pretty. It's mainly the reason why she treats Ella so miserably.
In Diana Wynne Jones's Howl's Moving Castle, Sophie becomes increasingly jealous of Howl's attempts to court Miss Angorian, a pretty teacher in Wales. However, when the Witch of the Waste kidnaps her to lure Howl out, Sophie goes out to rescue her, believing that Howl loves Miss Angorian and attempts to pull I Want My Beloved to Be Happy. Turns out Miss Angorian was the Witch of the Waste's fire demon and that Howl loved Sophie the whole time.
Used in A Song of Ice and Fire as part of the complicated Psychotic Love Triangle that forms the backstory of the Tully Sisters and Petyr "Littlefinger" Baelish. Lysa is jealous of Catelyn for being the object of Petyr's (unrequited mind you) affections, whilst Petyr is jealous of Brandon and ultimately Ned Stark for wedding Catelyn. Both characters take this envy to extreme, Yandere levels, resulting in Petyr manipulating Lysa into becoming his accomplice in kicking off a continent-wide civil war.
Bonus points for Littlefinger actually having Green Eyes.
In Suzanne Collins's Catching Fire, Peeta confesses he feels this about Gale.
The Sherlock Holmes story The Adventure of the Cardboard Box is about a murder which resulted from jealousy. A woman fell in love with her younger sister's husband, and when he rejected her (because he loved his wife), she conspired to get her sister to have an affair with another man.
Caroline Bingley is venomously jealous of Elizabeth Bennet in Pride and Prejudice, because Mr. Darcy clearly admires Elizabeth and is completely oblivious to the fact that Caroline wants to marry him. In her mind, at least; while Darcy clearly admires Elizabeth from early on, towards her it's suggested that he's adopting the time-honoured 'ignore-her-and-maybe-she'll-go-away' approach.
Also in the Jane Austen universe, Jane Fairfax rejects efforts by Emma Woodhouse to be friendly, because she's secretly engaged to Frank Churchill, who pays attention to Emma as part of the coverup, and even though she knows Emma's completely out of the loop she doesn't like it. Later, after The Reveal, she does admit to having been totally unreasonable about it.
And meanwhile, Mr. Knightley is hideously jealous of Frank Churchill for the same reason, because he's secretly in love with Emma.
In Daddy-Long-Legs, a man who is in love with Judy (Jervis Pendleton, aka Daddy Long Legs) tries to keep her away from Jimmie McBride, whom he mistakenly believes is his rival.
In Memoirs of a Geisha, it was Pumpkin's jealousy (along with a healthy dose of her mentor's influence) of Sayuri's popularity that would eventually cost them their friendship and would lead Pumpkin to betray Sayuri at a crucial moment.
In Robert E. Howard's "The Shadow Kingdom", Kull envies the lack of formality at the Pictish banquet.
In the Chinese Cinderella story Bound by Donna Jo Napoli, this was why Xing Xing's Wicked Stepmother treated her like she was a slave. Xing Xing's mother's last request was that Xing Xing would take care of all her father's needs more than anyone else, which she happily did and her father loved her more than the stepmother and his stepdaughter. In some ways, Xing Xing was closer to her father than her stepmother was to him.
Green eyedOzonne of the Disgaeanovels is jealous of her big sister Flonne because of her fallen angel status, her disposition in the Netherworld and their parents favoritism of her.
Lalla Moore is envious of Harriet Johnson's skating ability in Skating Shoes.
Susie Peters and Mimi Barron are envious of each other's dancing ability in On Your Toes, Susie!. Oddly, neither realizes how the other feels.
Bee Bye Simms is envious of David Perrin's riding ability in The Horsemasters.
In the Anne of Green Gables series, Anne is jealous of any girl who gets too close or mentions they would like to get close to Gilbert. She doesn't recognize this as jealousy, and frustratingly, it doesn't lead to a Love Epiphany, though everyone else can see she's jealous.
Morgan Sloat in The Talisman is driven by equal parts envy and ambition. By the end, they and the even worse Morgan of Orris have completely consumed him, leaving him a threat to the entire multiverse who cares for no one.
Harrison Bergeron is about a society built on appeasing envy in the only logistically possible way—reducing everyone to ciphers.
In Gene Stratton Porter's The Song of the Cardinal, the cardinal envies the other birds while awaiting a mate.
he envied the blackbird his glossy, devoted little sweetheart, with all his might. He almost strained his voice trying to rival the love-song of a skylark that hung among the clouds above a meadow across the river, and poured down to his mate a story of adoring love and sympathy. He screamed a "Chip" of such savage jealousy at a pair of killdeer lovers that he sent them scampering down the river bank without knowing that the crime of which they stood convicted was that of being mated when he was not. As for the doves that were already brooding on the line fence beneath the maples, the Cardinal was torn between two opinions. He was alone, he was love-sick, and he was holding the finest building location beside the shining river for his mate, and her slowness in coming made their devotion difficult to endure when he coveted a true love; but it seemed to the Cardinal that he never could so forget himself as to emulate the example of that dove lover. The dove had no dignity; he was so effusive he was a nuisance.
In A Reluctant Queen by Joan Wolf, a retelling of the story Esther from the Bible, King Ahasuerus's close friend Haman grew jealous of Ahasuerus's new wife Esther, with whom the king was deeply in love. He also grew envious of Coes, another close friend of Ahasuerus, when the king had summoned Coes during an assasination attempt on his life but not Haman. And his jealousy towards Esther's uncle Mordecai, whom the king grew to like, would eventually lead to his own death.
In a trilogy series called Dogs Of The Drowned City, Shep's friend Zeus gets jealous because Shep seemed to care more for the smaller dog breeds instead of him and the bigger breeds. Shep had only cared for the bigger dogs and himself more than the "yappers", but he sees that they need his help too. Zeus calls him out on it, and this causes him to run away from the pack and form one of his own.
In Michael Flynn's Spiral Arm novel In the Lion's Mouth, Ravn recounts how she seduces Donovan to give them a pretext to talk, and Bridget is furiously jealous despite not having any oaths between them, and despite her long having used such a tactic.
The happier state In Heav'n, which follows dignity, might draw Envy from each inferior; but who here Will envy whom the highest place exposes Formost to stand against the Thunderers aime Your bulwark, and condemns to greatest share Of endless pain?
In C. S. Lewis's The Four Loves, he discusses how this trope is common with either erotic love or affection; agape is needed to withstand it.
In the Deryni works by Katherine Kurtz, Conall Haldane becomes envious of his cousin King Kelson's political and magical power, and he covets Rhothana Nur Hallaj, partly because she's a beautiful princess, and partly because he knows Kelson loves her.