Craven...I think the final question is "Don't you deserve more than this?"
Your BF may be a sweet upstanding guy, but he's also an addict, in total denial about his addiction, who cherishes his #1 love above all else: booze. Do you want to continue being second to a bottle?
And yes, leaving him now would mean that you're some kind of "Super B*tch", but then leaving him in a month would mean you're also a "Super B*tch" for doing it before Christmas, and a month after Christmas, there's Valentine's Day, and then Easter, and then summer vacation, or a birthday, or the anniversary of his favourite zit popping....Point being, people will say what they will say and there's always some excuse why you should've stayed.
BUT, people aren't YOu and they don't have to live your life with an alcoholic, which, if I may say so plainly, ain't rosy at all.