Right, he is miserable, so I wouldn't go back. He is going to keep breaking up and coming back not allowing you to make any decisions, ever.
Just don't talk to him for a while and see how you feel. I think you are attached, and not in love at this stage. Love was gone out of the window in the moment abuse entered the door. x
If you start feeling better, then you know it was just attachment you were feeling, which is what I suspect you are feeling now.
I'd give it a couple of days and see how things go, I am sure you'll get some detox regime going on and life will slowly smile back again.