A

“Depression is a painfully slow, crashing death. Mania is the other extreme, a wild roller coaster run off its tracks, an eight ball of coke cut with speed. It's fun and it's frightening as hell. Some patients - bipolar type I - experience both extremes; other - bipolar type II - suffer depression almost exclusively. But the "mixed state," the mercurial churning of both high and low, is the most dangerous, the most deadly. Suicide too often results from the impulsive nature and physical speed of psychotic mania coupled with depression's paranoid self-loathing.”
― David Lovelace, Scattershot: My Bipolar Family

“Did you really want to die?"
"No one commits suicide because they want to die."
"Then why do they do it?"
"Because they want to stop the pain.”
― Tiffanie DeBartolo, How to Kill a Rock Star

“People pontificate, "Suicide is selfishness." Career churchmen like Pater go a step further and call in a cowardly assault on the living. Oafs argue this specious line for varying reason: to evade fingers of blame, to impress one's audience with one's mental fiber, to vent anger, or just because one lacks the necessary suffering to sympathize. Cowardice is nothing to do with it - suicide takes considerable courage. Japanese have the right idea. No, what's selfish is to demand another to endure an intolerable existence, just to spare families, friends, and enemies a bit of soul-searching.”
― David Mitchell, Cloud Atlas

“Simple. I got very bored and depressed, so I went and plugged myself in to its external computer feed. I talked to the computer at great length and explained my view of the Universe to it," said Marvin.
"And what happened?" pressed Ford.
"It committed suicide," said Marvin and stalked off back to the Heart of Gold.”
― Douglas Adams, The Ultimate Hitchhiker’s Guide to the Galaxy