I understand about the roommate thing. That's really messed up that he's beating up his girl, and good for you for standing up to him. He needs help, but he has to make that choice. As for you and your drinking...
You know, it makes it worse. I used drugs for years dulling my pain, and I lost a lot because of it. If you can't stop drinking, try to find a meeting. AA meetings are everywhere, and they help.
Don't beat yourself up. You can get better and get back on your feet. It sucks and I've been there; I've started a whole new life for myself and it's not always freakin' sunshine and lollipops. I'm a cynical as they come. But sometimes I have to kick my own butt too, and get up face crap. It sucks and it's not the be all end all, but being around people who've lost a lot can help you realize what you have.
I wish you the best.