I need support ( dealing with a cheating fiancé and baby due soon)

I am having a hard time moving past my fiancé’s cheating. He cheated on me multiple times when we were going through a rough spot last year from May - September. I don’t think I can move on. He created a dating profile in June two days after we got our first apartment together, he got snaps of a girl in a bikini with flirty tag lines like I can still see the lines 😘, he went to a bar with a bunch of his friends that are girls and never told me I found out from someone I was raking photos of because I’m a photographer, than the cherry on top of the cake he cheated on me in September with a girl when he was on shift work. Worst part he lied to me and said he was going to sleep but when to her house and it’s so fresh in my mind. We have a 18 month old daughter and our son due in June. Which I found out I was pregnant with our son 2 weeks after I found out he cheated on me...... it was like a punch to the face I will be honest I didn’t even want his baby at that point but feeling guilty, I kept the baby and tried to suck up my pride going it’s just for now I won’t regret it later. So I kept the pregnancy but have been upset about it since I got pregnant. I never connected with this pregnancy no matter how hard I tried. It has a huge deal to do with my fiancé. I stayed with him in hopes we could patch up the relationship. But I’m sitting here insecure, scared, always have my walls up and I don’t. Love him like I used to I sit a lot of respect for him. We moved 2 provinces to be closer to my parents, and that was huge because he has never moved in his life. But I can’t get over the affair we have been together since highschool, I get we were fighting a lot, we were new parents and things were really rocky but I don’t know how to handle this I feel so guilty for thinking this baby was a mistake....... but I’m not ready to be a new mom when I’m still trying to get past the affair he had. I just needed vent and I’m not sure if anyone else has gone through this and related the relationship. He hasn’t cheated since that affair but I am having trouble coping with it.