Hmm, how did I know I'd be responding to this thread? 
I guess I've said a lot about it in the past, but my main issue in life is that I can't seem to get into a decent, healthy relationship with a woman. Not that I'm incapable of this (I tell myself), but that for reasons that stem back to my early adolesence I've just never had the confidence to go out on a limb and put myself out there (except on a few occasions, which always ended with more awkwardness between me and the lady I cared for than anything romantic). 
What keeps me going and from giving up completely is the belief that there has to be someone for me. Or someone willing to put up with me. I'd hate to end up with someone who settled for me (that's my one condition, I guess).
Of late, this belief has been tested by my current situation: I started working at a new store in August, during the first few weeks of which I met the woman who currently has dibs on my heart. We hit it off immediately, then I heard through the grapevine that she had a boyfriend of several years that no one I talked to believed would break up with anytime soon (word of warning: it's never a good idea to ask co-workers about your chances with someone. For some reason they never think so). So I'd take pleasure in the little moments we'd have together at work, and try to hang around so maybe she'd see more in me than most women seem to have seen during my previous twenty-six years on this planet. 
So when she told me she'd broken up with said boyfriend a week before Christmas, I felt great. Then she started going on about some new guy she was already dating. Cue the banghead smilie 
And then there was yesterday and my aforementioned hasty exit from the 1,000th time I've had to hear someone I care about bitch about some guy who treats her like a doormat emotionally while I'm sitting there. 
Why don't I give up on her? Possibly because I'm stupid; possibly because up until I started college, work was the only place I met women; possibly because I have a rare disease that forces me to be attracted to unavailable women. Or it's possibly because I figure we'd be good together if I could just get off my ass and tell her any of this.
My point is, and I realize it's a cliche, but "don't give up" works for just about any circumstances. I don't mean "don't give up drugs" or "don't give up riding in the car with your torso out the window" or some sort of activity that could be dangerous and illegal, but don't give up on life. Sure, it's shit sometimes. But it's the shit times that make you appreciate the little moments when everything is right with the world, when a girl with the prettiest blue eyes you've ever seen and the nicest "no teeth showing" smile seems to think you've just said or done something funny and laughs because of it. Because you got to have something to help you get through the day.
That's my two cents, anyway 