Whether he is an alcolholic or not is in a way irrelevant. His drinking is a problem in your life, therefore its a problem whatever label gets slapped on it.
Stick around, learn as much as you can about alcoholism and what it does to those who love the A in their life. You cannot change him. Only he can do that. But you can change how you respond to his drinking and take care of yourself regardless of what he does.