In Naruto Veangance Revelaitons, Naruto commits suicide out of jealousy toward Ronan after Ronan catches him having sex with his wife Sakura.
In My Immortal, Draco commits suicide at one point, leading Ebony to attempt the same. Draco is alive the next time he's mentioned.
In MGLN Crisis, Raquel Benna commits suicide after telling Fate the truth about her origins, not wanting Fate to have to arrest her.
Shockingly enough, this happens to Meta Knight in The Dream Land Story. His one goal was to destroy Dark Matter, and kills himself after Kirby beats him to the job.
In the fanfic The Best Night Ever, Prince Blueblood goes through a phase where he kills himself in ever more elaborate ways due to Sanity Slippage caused by being trapped in a Groundhog Day Loop that forces him to relive the day of the disastrous Grand Galloping Gala over and over and over again.
The plot point in the infamous Axis Powers Hetalia fanfiction Behind the Mask.
At one point in Fire Emblem Fates fandom it was popular for Corrin to kill themselves during the big choice between Hoshido and Nohr. This was portrayed as a tragic act of love on their part, with their families mourning their loss and declaring them Too Good for This Sinful Earth. One author found it completely OOC, however, and mocked the hell out of it in their fic.
