He doesn't get mad but he'll still keep going on about it. I'll say, "I let it go, it's in the past" and he'll just dismiss it by saying, "I know but still...." and just keeps going on about whatever it is. When I'm officially on my own completely then I can avoid that more often. There may come a time where I just have to flat out tell him to stop talking about it and walk away, may be the only option even though it sounds rude and disrespectful.