He will absolutely cheat on you again. The only absolutes in life are death, taxes, and that creeps who cheat on you, get the girl pregnant, and then turn it back on you will definitely cheat on you second time. Why haven’t you dumped him already? Why aren’t his clothes strewn across the lawn? Why isn’t his head swollen from the anvil that you dropped on him from the top of a building? Why do you want to have anything to do with a guy who would get another woman pregnant and then somehow blame it on you? Why haven’t you left him to deal with the mess he’s created?
I’m amazed by this guy’s level of self-delusion. “How was your day, honey? Great, great. Hey, guess what? I’m cheating on you, and the girl’s pregnant. Oh, and P.S., it’s all your fault. What’s for dinner?” That’s some serious Don Draper/Talented Mr. Ripley style sociopathy right there. How do you spin something like that back on your girlfriend? I wonder how people like that sleep at night.
There is nothing to work out here. Why do you want to be a part of the drama he’s created? If he was apologetic, and confessed to cheating on you and knocking up the girl, even then you’d have more than enough cause to dump him. But the fact that he tried to blame you for all the terrible things he’s done? That’s a guy who will make your life miserable without an ounce of remorse. I could see you being conflicted if it was a one time thing and he was freaking out about the mess he’s put everyone in. It wouldn’t make what he did okay, but at least he would seem like a human being and not a psychopath. In a way, it’s better than he acted the way he did. Now you should have no trouble walking away from this mess.