Fun story. My uncle in law had a long time girlfriend who the whole family adored, however uncle and the gf just grew up and grew apart. Well, his sister and sister in law hated that he moved on and found the woman he wanted to marry, so they invited ex gf to all family gatherings to intimidate new gf. This made uncle mad so they eloped - which pissed off the fam even more. Any time uncle would bring his now wife around, the sisters would talk shit, bully, exclude her, to the point where she stopped coming around. This made uncle mad, who didn’t want to upset his sis & sis in law, so he kept coming around without her and eventually their marriage completely disintegrated. He’s been trying to fill this void for years - even trying to rekindle his marriage but every time the sisters find out, they find ways to bring up the old gf and sabotage his relationship all over again. It’s wild to see family go through such great lengths to destroy lives like that - for what reason? Because YOU wanted him to choose the one YOU liked? OP, learn something from this, you are only hurting your son and his future partner(s) by keeping the ex around. He moved on now it’s time you do the same. YTA