First two are from experience, second two are from anecdotes whose sources I mostly forget plus a dash of experience.
I don't have nearly as much experience with suicidal thoughts that can be interpreted as "wanting to die", but I can report that the standard "too much suffering to cope with" explanation isn't universal.
Link
One of us is no more.
He deserves a eulogy more eloquent than what I am capable of writing. Here's Cory Doctorow's, one of his long time friends.
It's a sad world in which you are being arrested and grand jury'd for downloading scientific journals and papers with the intent to share them.