Alaia,
First, I don't know why the hell his new "girlfriend" (or shall I say victim) felt the need to tell you all of this! Completely inappropriate, especially since she is STILL with him!
Ugh, I do not understand why you would have stayed with him in the first place. I guess love can work in mysterious ways, but it sounds like you were more codependent and he was a typical selfish addict. That isn't love, nor is that a relationship!
Be thankful he isn't your problem any more, he's the new girls' and his own. I know it sounds harsh but mourning over him not being in your life any more would be foolish, you should honestly be celebrating!
Stay safe,
Rachel