My ex husband keeps showing our 6 years old son photos from before divorce, including holidays, wedding etc. He also tells him how I moved out from the house and that my little one’s stepdad is nothing more than my boyfriend. I repeatedly asked him to stop doing/saying this but no results. My little one gets upset and asks questions about the past that he shouldn’t be worried about. How can I deal with the ex husband, is what he is doing a psychological abuse?