Some people recover, some don't. It usually has nothing to do with the person they're in a relationship with--they just get sick of feeling like crap and having everything in their lives suck so they get sober--if they do the work and have the commitment they'll stay that way. If not, they won't.
It sounds to me as if you secretly HOPE she will, that she will want you so badly that she will do anything--even changing her life--to get you back.
I wonder how your current g/f would feel about that? I'd suggest letting the alcoholic GO. Even if she were to get sober--go to rehab, go to AA, whatever--it will only stick if she's doing it because she desperately wants it for herself, not to get you (or anyone else) back into her life. Let her find her own path, and you concentrate on your own.