This is gonna be stupid long but I have to explain....

Me and dude meet August 2016 he’s going through a divorce that’s pretty bad but assured me they are done blah blah, everything’s pretty much great the first year we jumped into things pretty fast and was kinda like if we get pregnant we do so I got off the depo shot November 2016. We move in together August 2017 and instantly things go bad he’s being controlling whatever so then we move to a different house and I find out he cheated on me June 2017 but times passed and he has a excuse that I give in too... his ex wife didn’t know about me until October 2017 which I was fine with cause I could tell she likes drama... she finds out about me on thanksgiving November 2017 and messages me and threatens me and tells me they still are messing around and things like that.. I believed him over her, things are good with us but she keeps telling people I’m coming in between her family and her marriage cause all of a sudden she doesn’t wanna get divorced anymore when she finds out about me. She’s spreading rumors about me saying I’m abusive to their son who I absolutely adore... she keeps texting my fiancé saying give me a baby and a marriage or I’m divorcing you foreal... finally April 2018 the divorce is final and we celebrate, she texts him the day of the divorce apologizing saying I’m sorry but I had to do it cause you picked her over me. We’re getting his son regularly and things are going good but then his son starts asking his dad why him and mommy sent together anymore and can he come home... totally out of nowhere. I see my fiancé text her on their ex anniversary saying he was sorry for everything and she’s a great mom and more and he’s trying to do better for their son blah blah. She keeps posting publicly on Facebook claiming he’s saying he wants to come “home” idk why to believe so I start questioning him. He denies it... I got so stressed out from all her crap that when October 2018 came we had a falling out and he left that night... I wanted to make sure he was okay so I called his mother the next day and she informs me that him and his ex wife are trying to make it work for their family and I should stay away. So I did that... I packed as much as I could and I went to my moms house and sulked, he eventually calls me and is crying says he didn’t sleep with her he’s been on her couch he misses me he made a mistake blah blah I told him I don’t believe he didn’t sleep with her but we were broken up so he needs to figure out where we go from here. He says he wants me and to work things out but feels bad about leaving his son so I gave him some time to get it together and she contacts me asking if me and him are talking I told her yes and she claims they’ve been sleeping together this whole time he’s been back like almost every day! So she calls and I mute the phone and she questions him then I hop on and he starts crying and she makes him admit EVERYTHING like the fact that the whole first year we were together they were still having unprotected sex and she got pregnant in July 2017 and had a miscarriage and all the things he’s lied about just comes out over he phone. I told him I’m done and hung up... now neither one of them will leave me alone she’s trying to be friends and I’m like no I’m good foreal. I see him again cause we had to get our things from the place we were staying he’s crying hard I feel bad whatever gave him my new number and told him to figure it out, he gets a new phone and instantly starts contacting me he we go again she wants to know if we’re talking I tell her yes she’s trying to kick him out every other day they’re abusing each other it’s stressful. So he gets it together saves up money and tells me come get him and at this point we live 3 hours away so I did and he moved in and things were going okay. Then I find out she’s pregnant ... due in August. We found out it was a boy today... she wanted a abortion but he threatened to tell their son about it if she did so she chose not too. I’m hurt I’m mad I’m sad I’ve been struggling with getting pregnant and they are about to have another baby... he can’t own up to why he has done to me and how bad he has hurt me I can’t talk to him... we used to be best friends and more and now idk who he is and I don’t have the heart to make him leave again because I do love him. She’s rubbing this pregnancy in my face and it hurts so bad idk where to go from here. I’m 22, she’s 29 he’s 30. What could I have done to deserve this? I wish I could go back in time cause I’m stuck.