Can’t get past the hurt

My SO and I have been together for a long time. We’ve had an off and on relationship. (Always his call for us to break up) he started choosing drinking and his friends over me. I’d beg him to come home every single night but he’d stay out later. He wouldn’t come home until 3-4 in the morning sometimes 5-6. Literally every single night. (This was during covid lockdown so it was super hard for him to find a job) I wasn’t strong enough to leave.. we have kids together so I know some women will understand. But he wouldn’t help me do anything around the house. Not even help me with them. (He was also gone most of the day). Now. Years later he was still going out when he didn’t have work the next day or if he got laid off he was out a lot again. Doing the same stuff. Drinking and choosing his friends over me. And of course I was telling him all this time how tired I am of it and I couldn’t do it anymore. I finally had the strength to leave and he all of a sudden wanted to do better for me. So I gave him another chance because I felt he was sincere. It’s been a few months since I took him back and he has honestly done better! He hasn’t gone out but a few times (which I was okay with. I’m okay with him having a night out every once in awhile) but I still can’t get over the hurt he has put me through in the past. I’ve tried but I don’t know how. I found out while I was pregnant a few years ago that he was talking to others. (He claimed we weren’t together but he damn sure acted like we were) but anyway. I just want some advice on how to get past the hurt. There’s alot more I could say but this post is already long. So far he has done good for our relationship and it’s not fair to him that I’m stuck in the past. He has apologized many times. I feel like I have resentment built up towards him