He's trying to fix our relationship but is it too late?

Lee

I've been with my fiance for 5 years engaged for 3 years. From the beginning we had a very rough start because of the relationship I had with my mother she has mentally and emotionally abused me since I was 5 years old. Dealing with that on my own has took its tole on me as a person he doesn't understand how traumatizing and hurtful it is to have your mom treat you like crap your whole life.  When I was 5 months pregnant with my first his crazy ex decided she wanted him back. He told me he didn't want her but never did anything to make her go away  instead he would avoid where she worked (she worked inside the mall )so every time we go to the mall we had to avoid her area. When I would get into it with my mom he basically made it seem like it was burden to deal with any of my problems  but when he has his down days expects me to be understanding of him. Whenever we would argue he'll either be in a drunken rage where it's everyone else's fault except his he'll verbally abuse me and then say he didn't mean it when he's no longer upset. He has physically cheated on me and I've also caught him on Facebook flirting with other girls. He doesn't help with our kids but he has plenty of free time to do whatever he wants without having the kids with him I'm a stay at home mom I never get a break not even if I had surgery. He's never happy content or comfortable  he has a good paying job but doesn't want to work for someone else but yet he doesn't know what he wants to with his life we don't go out as family we do don't do things as family he honestly would be happy if he was alone no responsibility  and doing whatever he wants he says that's not true but his actions show otherwise I've talked to him about how I felt when problems arise he would either change for a short period of time or dismiss my feelings like I'm always attacking him I'm currently pregnant with our 3rd child and I don't know if i can do this anymore he use to treat me like a queen, supportive, loving  now if I cry it doesn't phase him. Since he has cheated sex doesn't mean the same to me and now that's the only affection I get from him all he does is talk sexual touch me sexually even though I told him I want to cuddle and be around each other without it being sexual or turning on to sex instead of sweet messages i get sexual memes and after we had sex then he won't touch me. I'm to the point sex disgusts me I had sex and I'm sure it was obvious I was faking so I try hard to avoid him  i.feel nothing when we kiss when we hug  I don't miss him I use to fear being a single mother but I feel it would be for the best I don't even want to get married anymore   I forgave him so many times for hurting me that I think I'm tired of trying and not getting anywhere I don't feel loved me and the kids haven't been out the house in weeks all he does is get drunk play the guitar go to work and sleep we have a talk about all this and he said he would try but I don't know if it's worth it to try anymore

Sorry for the way it's written tried to sum up 5 years of our relationship really fast