What now?

I have delt with severe depression and suicidal thoughts since fourth grade (now 18). I went through everything from self injury to trying different ways to kill myself. I've been to different therapists, groups, and hospitals trying to get better. I've always been heavily dependant on drugs and alcohol to get through my days. About a year and a half ago I started drinking constantly to forget all my problems. Just a few months ago I finally slowed down and now I'm seeing all the damage that has caused for myself and everyone I loved. I lost everyone, including my family (disowned me) and my boyfriend of four years. I have been choking back my feelings because I know if I don't I will end up doing something stupid and also because I've learned if I keep my mouth shut then everyone seems to think I'm completely normal. Everyone thinks I'm "fixed" but I'm still the same inside... I feel dumb, like I should have grown out of this by now. I have a great job and finally got my life together but still the pain I've bottled creeps up on me every now and then... I'm afraid I might explode one of these days. So my question is this: How does one overcome depression/suicidal thoughts? I don't want to cry anymore.

I wish I knew, as I deal with depression/suicidal thoughts daily....