no i never heard my dad gossip about me, he was an alcoholic and the only thing that came out of his mouth was "get me a beer". It's horrible that your dad gossips behind your back and with him being the adult and the parent he is going to kill your self esteem and pride and you do not deserve that at all. I think the only way your going to break him of doing that to you is to confront him when you hear him gossiping on you or start keeping a journal, leave it out in the open where he will read it and make sure you put some strong statements in the journal like.... " I heard my dad gossiping about me and it broke my heart..... I do not understand how he could be so mean to say things behind my back.
On a more positive note, Lift up your spirits and be proud of yourself for who you are and ignore his childish gossip , obviously he is the one who has the issues, not you.