Pregnant with cheating spouse’s baby

How did you enjoy you pregnancy if at all, after you found out SO cheated on you? I left my fiancé after finding out he cheated and got another woman pregnant. The woman is 5weeks and I am 16weeks3days. I’m completely devastated. He begged for me to give him a chance but I refuse. The woman keeps harassing me telling me she’s sorry and she shouldn’t have slept with an almost married man. This man promised me a better life and relationship because I had gotten out of an extremely abusive relationship. Tw.. my ex raped me and I conceived a daughter from him. He was in jail for months but was recently let out on a program. Now he’s harassing me too. I want to take my kids and move the next state up but I don’t want to be that bitter baby mother that takes her kid away from her dad. My abusive ex I don’t mind because I have full custody and he’s a psychotic person but I’d feel terrible leaving my ex fiancé while I’m pregnant with his baby. People tell me I shouldn’t feel bad and he deserves it but I also can’t do that to my daughter. I don’t want to run away from these problems but I also don’t want a romantic relationship with him it all. How can I make this work? Do any of you have experience with this? I’m sorry if this doesn’t make sense, my mind is in shambles (and yes I’m leaving him/not dating him anymore. I just need to know how I make our relationship/friendship civil enough for the kids)