Dude tell her you are ok with her having a boyfriend and you want to stay together. I have doubts on the authenticity of this since you first mentioned a child and since have said nothing about babysitters or grandparents or how this will affect the child. However if it’s true stay together for...
If you have a wife or girlfriend that isn’t cheating it would be unusual. All women cheat as far as I’m concerned. When I was younger I banged 12 different married women and all were the type that would never do that sort of thing lol.