RLay, this is all part of the routine. The simple answer to your question about him being after other women is, he simply doesn't care. He is totally selfish and that isn't going to change for quite some time, if at all. Of course he is going to blame you for everything, he will not take responsibility for anything. This is also not going to change anytime soon, if at all.
It takes people many years to snap out of these things. What usually snaps them out of it is a bad situation. So it will have to be a bad date(s), that causes him to evaluate his life at this point. He may see that he was being stupid, and actually wasting time passing through all the different women, agenda's, problems, etc. Like I said it takes along time for it to happen.
I wouldn't wait on him if he's continuing in that direction.