Can't get over the fact that he cheated.

I've been with my fiancé for 5 years and just recently we went through this "phase" where he had another girlfriend on the side. They never met face to face but i caught them talking 3 times. Telling eachother they love eachother and talking about having babies together. But each time i forgave him and took him back only to find him talking to her again. The last time i caught him I was beyond depressed. Ended up in the hospital for 3 days on suicide watch. I was 6 months pregnant and woke up bleeding one morning while i was in the hospital, my doctor said it was from the amount of stress i was under. After that he vowed to be loyal because he never wanted to see me like that again. I took him back and things have been so different. It seems like he loves me more, hes on his phone less and even lets me see it whenever i start to feel insecure. I know that doesn't sound like a healthy relationship but hes the father of my babies and I want to make things work. I dont know if its because im at the end of my pregnancy and im super hormonal or what but I think about what he did everyday. I want to break up with him so he can be alone and feel the pain i felt while i sat in the hospital. I want all of this bad for him but at the same time i just want to love him and have him love me back. I can't get over the hurt and idk what to do..