Do we have to go to court for mediation or can we do it on our own?

My 14 year old doesn't want to spend time at her fathers house because he has serious control issues that cause fighting constantly. It has become unhealthy for her but I know the complaints are not enough to take her away completely. Not sure which direction to pursue to change this situation. She comes home crying every weekend and she is not that kind of person. She is to afraid to tell him she doesn't want to go there because even an outfit she wears can enrage him into a battle. She is not a rebellious teenager, but I'm worried the stress of being constantly told how awful she is by him is causing serious damage to her self esteem. She wants things to be better with him but he refuses to accept he is doing anything wrong. He tells me I'm trying to be the "cool" mom by not upholding his punishments at my house, but I don't agree with him and he is still trying to control me even though he has a new wife to control. Please help!