To be honest, the best thing you can do for your boyfriend is do something for yourself first. You cannot make him do anything to change himself, as you have realized. I would suggest that you find a Al-Anon group and start going to meetings there. There you will receive support, information, and knowledge that you are not alone. You can be healthy which your boyfriend may see as a threat to his alcoholism, so beware of that. His behavior may change towards you as he sees that you are going to do something positive for himself and stop taking care of him and making excuses for him. May you gain the strength to follow through on not supporting his drinking and behavior and violence when he is drinking. Only he is responsible for all that - not you. Not ever you. Find someone you can trust and talk to that person. Someone like a counselor or a minister - someone who has received training. Someone who will listen without judgement and be a good shoulder and resource of information.
Find some literature/books/articles on co-dependency. There are online resources to check out also.
Codependency & Recovery from codependent relationships
Codependence/Codependency=A Spiritual dis-ease, disconnection from Spiritual Self (a five part series)
Congratulations on making the decision to become emotionally healthy. You have a tough battle ahead but you can come out ahead and the insight you will gain in the process will keep you in good stead. The very best to you.