It may just be a kick up the ass for you. She hasn't said "lets have a 3 month break", just to come back to a relationship when it gets better.

But a break wont make it better, it will make it worse. You won't change your drinking habits, you'll settle down living apart and never want to get back together. If you want to maintain this relationship you need to tell her that a break is stupid and that you will work on your problems starting, not even immediately, start it freakin' yesterday.

If you dont want to work on your habits (which is fair enough) then she isnt the girl for you.