Relationship problems

little

Ladies I’m done I tried to give my BD another chance I really did but he dose not change I’ve sat and talked about what we can try to fix and learn together but nope he’s still the same I’m not gonna be the only one do try . So ladies I need help, how do I tell him I’m ready to leave ?we have a child together I wanted my son to have both parents together growing up but I’m not happy and it seems selfish to me if I just get up and leave and break our home but I know it’s not good for me or my son to be in a unhappy home . I do I tell him i wanna leave and be happy for myself because believe me he won’t understand even if I said it straight out to him.