Ex has me and new gf pregnant

Amber

I just found out that my ex has his new girlfriend pregnant. He kicked me and my son out at the end of December and moved her in. He'd been cheating since November and had told her he was single and we'd broken up in August. He's running around telling everyone that I'm a slut and it's not his baby (even though I've only had sex with 2 guys in my life and the other was one time when I was a teenagers .) So it's obviously his and he knows that. He's been involved in my pregnancy and gone to ultrasounds.

I was under the impression that his girlfriend had been aware that he was with me when he was cheating (he told me this) so I've still off and on been having sex with him feeling like it didn't matter because she did it to me. (I know I should have blamed him which I did but obviously not enough). Well in the past few months I've gotten sick of him trying to keep me wrapped around his finger and have been trying to break away but he'd beg and plead with me. I finally told him he needed to tell her everything and he agreed but I sent her proof because I didn't believe him and blocked him. I was done with it all but I feel like he shouldn't be able to keep lying and getting away with things. She ended up messaging me and basically everything he's told me and her are lies. I find out that we're both pregnant by him 8 weeks apart and he's been hiding her pregnancy and denying mine behind my back. They've been looking at rings and planning on moving out of state and when she asked what about the son me and him have together, he said they're starting a family and that's his priority now. He's also been lying and saying I don't let him see our son when he comes over here and sees him whenever he wants (which honestly isn't a lot but that's not my fault). The only times he even comes around to see his son is if he's getting sex from me. But even though I gave her proof she went back to him which I think is stupid but I can't judge because I kept going back to him every time he cheated over our 8 years together. He's very good at saying everything you want to hear and I guess she's just going to have to learn the hard way like I did. But now that I told, he has deleted his Facebook, changed his number, and hasn't tried to see our son. I honestly think this might be the moment where he disappears and completely abandons his children. I just feel like my situation is really fucked up and it'd be nice to hear if anyone has been in a similar situation.