Love can't make them stop drinking. If it could, this site wouldn't be here. You are in love with his potential, but you need to see who he is right now. This is who he is likely to always be. You can't save him. You can't fix him. He is abusive, and that's pretty likely to be something far beyond just alcohol. I'm worried for your safety. Please know that you didn't cause it, you can't control it, and you can't cure it. This isn't a Hollywood movie where he suddenly realizes how amazing she is and they live happily ever after. This is reality, which is far grittier and where she usually ends up hurt pretty bad.
Please don't go back. Do you have the number to the Domestic Violence hotline?