Welcome to the boards Duke.
I'm in similar shoes with an AW (Alcoholic Wife).
Seems like you have a massive heart and care and love her so much. I'm sorry to say this but for now, those baby eyes are nothing more than tools for the booze.
It's exceptionally hard to do but you need to try and direct all that love and caring towards yourself. That's the only way you will get better. Your wife will either get on board with your positive changes or she won't but in the end, you'll be learning how to love yourself.
If she is in fact pregnant, I'd be making sure I went to her checkups. That doctor needs to know that she has a drinking problem because she will be lying for sure on the form she completes. yes. She will be upset and it will be a scene but for the sake of the child, the doctor needs to know the real deal.
I don't go to Al anon but I do read and post here. It helps me so much so stick around. You're not alone.