All of my children have had this problem. My mom tells this great story about how she went to visit her mom and her big sister, which she has never been fond of, was also there. They had a private conversation about her children. My mother said they were ugly. So what does my sister do the next day... she tells her that her children are ugly her mommy said so. OMG! My mom still tells the story but I can never imagine how mom got out of that.
Now my husbands father was abusive. My husband and me have talked about it with him obviously hearing it. So naturally my son, while we were over there, asked grandpa why he was abusive towards my husband when he was a child. My god was that a terrible dinner.
So you aren't the only one. I just had a very long convo about how talking about mom and dad's business is not ok and that things said about others in this house wasn't acceptable. Then with dealing with the more wide spread stuff like you talk about I told him that if it would hurt someone's feelings like to do with weight our appearance in general that he could hurt someones feelings and make them feel badly. I think we had this discussion 12 times before he got it. But eventually he did! Thank goodness.