Welcome to SR! Some good wisdom so far; I couldn't agree more with taking the focus off the alcoholic and putting it back on you and your baby. It's easier said than done, but once you do it, you will feel better.
None of us here have any magic answer on what to do with your BF; short of leaving the relationship to protect yourself. Sounds as if he intends to continue to drink, regardless. Acceptance of that is imperative; it is his choice, after all. Accepting your reality as it is right now, not how you would like it to be, is most important and also the hardest thing to do!
Take care of you and that baby! Keep coming back.
P.S. Fighting with an alcoholic is no different than fighting with someone with dementia. Huge waste of time, energy, and emotions on a pointless endeavor.