You do it because whatever is wrong with you sounds like the same thing that is wrong with me. I stopped dreaming a few years ago. You're self destructive dude. Your mind is your own worst enemy.
I haven't figured out the cure yet...but if I do I'll let you know. P.S. Drugs don't work. Booze...the jury's still out on that one. (for me at least...I'm not advocating self-medicating with alcohol...I just find that after a night of beers with some friends, I sleep like the dead).