Jeckil and Hyde

So my roomate is doing a very good impression of an alcoholic. I'm not really sure if I'm dramatizing this, he is going through a rough breakup, so it could easily be a phase. But there are a couple of things that concern me. First of all, he drinks every single night. Second, there is a real and recognizable personality change after the first few. Third, he does it to relieve stress, to help him forget about bad stuff that is going on.
At this point I'm not sure if there is anything I can, or should, do. I'm trying not to facilitate him. I don't drink with him when it seems like he's losing control, though I do have a beer or two with him several times a week. I suppose if I stopped drinking entirely in protest that might have some effect, but I feel that would be something of an overreaction. First of all, he's not yet into any really serious problems, nothing criminal, he's holding down a job, ect. Second, why should I modify my life for his sickness?
I think really what upsets me is that I have no control over the situation. I can't not spend time with him, we live together, so we're bound to see each other a lot of the time. I can't stop him, or even impress upon him that it is a problem. I'm basically helpless, which is probably what upsets me the most. I don't like to be out of control. This is probably why I'm not susceptable to the same problem, my hangovers are accompanied by enough guilt that I can't use the 'hair of the dog' to fix them. This quality is probably why I don't feel much kinship with him, I can't imagine going on a downward spiral like he is, my problems all stem from too much risk aversion rather than too little. I knew this about him when I decided to move in. It was a quality I wanted more of- the ability to take more risks. The fact that I'm seeing the worst side of that doesn't change that I need to learn more of it, but it might make it very hard for me. After all, emotionally, how can I model myself after someone when the precise characteristic I want to follow is the one creating a behavior I can't stand?

Maybe I should talk to him. I really should. He's very fond of plain speaking. I can use the fact that he punched a hole in the wall to bring it up. I really should confront him, and at least mention that I'm not too happy with the current situation. To think I moved in with this guy because my previous roomate was uncommunicative. The devil you know. So I guess I'll see.