Ironically, I consider myself a very optimistic person, but the thought has crossed my mind. I guess one factor would be that I consider life to be one large experiment that everyone participates in. We all want to learn more about ourselves, the world, and everything in it. There will always be the question about death hovering over us. Fortunately, we all will be granted the ability to learn what death is like eventually. It just takes patience and time. With that time, we have plenty to learn about every other question we have.
Suicide is more of an act of impatience than anything else. My personal goal is a search for knowledge. As long as there is more to be learned, I have all I need to continue. As far as the "My life sucks/ shitting pants" examples, what about this: Yes, your situation has changed, but is every day the same? For most people, the answer would be no. If it is yes, then you should reevaluate how you are living your life, not how you want to throw it away.
If you are dying of incurable cancer, than you should have even MORE reason to live and enjoy the time you have left. "Pfft, I don't give a shit about spending time with those that I love, let's just leave faster and never see them again." A little inconsiderate, don't you think? I'm sure that your death will come soon anyway, so enjoy it, learn with it, laugh with it, and cry with it. All experiences, whether good or bad, or experiences. You can't choose which ones you get, but all of them are worth something.
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