... I would greatly prefer my death to take place at a high point in my life.
Having said that (yourself), wouldn't you think that 'high' point in your life is simply... yet to come? This would most definitely mean you have a chance, a healthy (enough) outlook in the life ahead of you.
... Why do you think there are people out there (somehow) seeking martyrdom, for instance? Would it help you to think what drives such people to a cause that they believed in?
Look, what I'm trying to tell you is - you've come this far in life against all odds, which suggests you got what it takes. Odds? I would encourage to think about some people... a lot of people out there seeking a cause, which befits their rights, human rights. How they would leave their mark in history, how not to get caught up in the prejudice.
... Are you getting the 'hardcore' kind of living, here? What do you think you've seen or felt or been 'hit' by so hard enough, which tempts you to consider this act? I don't understand.
For what your conscience might tell you, there are pursuits and challenges out there that would test you, up to the point where you may 'think' about dying, but it'll be that exhilaration that keeps you on the drive.
... It's true, life can be tough, but you ought to realize that where there's worth - hope and fear more-or-less coexist. Bailing out is simply out-of-question, here.
Don't want to say I would know best in this regard, but I'm sure a lot of people have been in that road - perhaps they were suicidal at a point in their lives, themselves? Hope never fails, and people can be good even against the odds.