I'm right there with you. Just broke it off with my ABF. I finally just gave up hoping that he was going to get sober. After all we had been through, the pain, the misery, the disappointment, he told me that he didn't want to stop drinking. It was then that I knew it had to end.
And just remember, even if he's "with" somebody right now, alcohol is his girlfriend. He's in a relationship with drinking. It doesn't matter who is physically around him.