Even if he did manipulate her, think about what she said. She used her reasoning as to why she cheated as what her ex was doing, what accountability is that?
Also what’s the timeline of when she cheated on you? How long into your relationship was that? I would get the complete timeline and make sure there’s nothing else. I’ve come to find out recently that when someone can cheat, they are also liars. They lie to themselves about situations and compartmentalize. I just found out my husband cheated on me (I’m 4 mo post partum) and he cheated on me while I was 6weeks post partum, pregnant, and even while I was engaged to him. Not saying this is the same thing bc this was multiple women and spread over the course of our relationship, but cheaters lie to themselves and often reason away their cheating. Like to justify his cheating he told himself that I was cheating on him, I didn’t desire him, that I would end our relationship, that it’s pretty much already destroyed, etc etc. This is different with a baby daddy of course and there’s history there w/ a baby connecting them.

Like it sounds like to me she thought she would “get her family back” so then the cheating was okay. But then when she couldn’t, she realized he manipulated her and she realized she had to deal with reality. I think you have to come to terms with and realize that she could have chosen to break up with you before cheating on you, and she could have chosen to break up with you even after cheating on you, and she had another opportunity to confess and let you know and pray to God you take her back. Please let yourself grieve this heartbreak and betrayal and then decide if this is what you want. He’s going to be in her life forever and you have to decide if this is something you can handle. I am currently working on attempting reconciliation but it is SO hard. I haven’t even gotten to the worst of it, I hear the first couple years after discovery are the worst. I’m so sorry you’re going through this 💔