Should i have gotten involved with my ex-boyfriend and his current girlfriend now if it has to do with my fam?

Ok, so me and my ex-boyfriend broke up about 4 months ago because he cheated on me. With his current girlfriend now name Hannah. Hannah and me, have a past. Including our families. Our families never really liked each other. So couple of days ago she heard a rumor that my little cousin was talking about her and my ex-boyfriend. And Hannah cussed my little cousin out on my ex-boyfriends facebook page. So i called her out on it because i already didn't like her. And her getting involved with what didnt even have anything to do with her in the first place. Should i have said something?