How can make my boyfriend get help for his alcoholism?

I've been with this guy for almost a year and 3 months. I'm 8 months pregnant with his child. I have two other small children by two other men. My boyfriend lives with us and he was paying all the bills. He has been laid off for two months. However, he's an alcoholic. He's been an alcoholic since he was a teen. He's in his late 20's now. He is also having an affair with another woman he knew before he met me. In fact, they've known each other since high school. For some reason he won't leave her alone. He spends all his money on her.When I ask him about his drinking problem. He tells me to go f@ck myself. There's not a day that goes by he's not drunk. He reeks of liquor and he acts stupid. He lies in bed with a throw up bucket next to him every night. He always tries to kiss on me when he's drunk and I push him away. Then he tells me he can get better p@ssy somewhere else. He's only concerned about the baby so that he can get a big tax refund check. I am at a loss right now.