I’m confused about my relationship with my boyfriend/ baby’s father

So last night randomly he asked me if there was anything that I wanted to talk to him about or anything basically he said that he never checks in with me and he just wanted to. He said that he felt like our relationship hasn’t been the same for a while and I agree. I feel like we lost a lot of our fire and now that we live together I feel like there’s a lot more things to be irritated with him about and especially after having a baby I found myself just resenting him a little more which I’ve come to find out on this app is normal. However I just don’t know I really do love him and I can’t see myself without him but there’s just sometimes I wish I was single and I truly feel like he doesn’t understand me I’ve been dealing with severe anxiety since having my baby and he just doesn’t understand that so it’s really hard for us to relate to each other. I feel like when we were younger we used to be so in love and it just feels different now like I feel like I’m not in a relationship with the same guy I fell in love with. I really can’t see myself without him and I can’t imagine what it would do to him if we were to break up but I just don’t know what I’m feeling

Like we’ve had issues with him and other women and stuff like that not necessarily cheating but just talking to other women and there’s this one girl that comes up all the time like at least once a year we’ve been together for almost 5 years and she comes up all the time just the other day somebody sent him a message asking if he wanted to talk to her. And honestly that’s always on my mind like I just can’t really get over it. Like last night when he asked me if there was anything I wanted to talk to him about I had told him about that girl and he got really mad about it and didn’t even want to talk but he had just asked me if I wanted to talk about anything so I told him he says that he just talk to her but I truly think it was more than that and he just won’t tell me