Advice?

Has anyone felt like they’re slowly mentally checking out of the relationship? I’ve done everything to make sure my child has two parents in his life. I just don’t feel the love anymore. This man will never change, ever. After dealing with this for 4 years, I found him saving thick girls on his tiktok and sending the videos to himself. I guess i’m just mentally checking out. It didn’t even hurt. I was kinda like “oh, you’re STILL doing this?😅” and that’s when I realized that he’s just not ever going to change. Don’t get me wrong, he is a great father, very active and loves his child. But as far as being a boyfriend? He’s just not there. I actually feel odd that it didn’t hurt that he had those girls on his tiktok. Maybe i’m being dramatic but I think i’m mentally checking out and it feels weird. It breaks my heart that eventually my child will have to be back and forth with his father and I but what else am I supposed to do? Advice?