"My question is this... I know i can't fix her. I know it is not within my control. BUT, can i encourage her with positive behavior? Can I foster healthy decisions? When she does abstain, will being supportive of those choices help? Providing a safe haven... does it help if she is asking for help?"
from my experience of living with an alcoholic wife for the past 20+ years, no. You simply can't do the things you are hoping to do.
you are simply guilty of applying reasonable, and normal actions to stimulus. Your alcoholic gal is not reasonable. Nor normal.
you are absolutely correct, you can't fix her. You can try to encourage her, but in reality you are only satisfying your own need to do something. She will say and do anything. Lying is a way of life.
Sure you can foster healthy decisions. however, she will resent you. At some point she will lash out at you as the cause of her problems.
When you support her abstience, you will come accross patronizing. Certainly you can do it, but to what end? Why? What is the point?
Your safe haven is simply enabling her to do what ever she wants. Really. That is all it is.
You don't want to hear it, but here is what to do:
run away fast. Don't look back. Don't try to change her. it simply won't work. there are plenty of wonderful women to share your life with. It's just hard to find them in bars.