Child custdy?

i have a question for anyone. i have custdy of my 2 chrilden and their dad has every other weekend and my ex husband has told my daugter that is 5 she is 2 fat. my daugter is only 50 pounds know she has trouble eating. my son dont like going over their because their father is mean to them. i have went to the court and child proctive services with some of the things the chrilden has told me. i evan have them in counsling and the counsler has wrote many letters to and the courts still has done nothing. but the judge has told me if i dont send my kids to their dads i could go to jail. i love my kids and i am a very concer mother. the cort system wont help me and i am afaid something bad may happen to my kids with this abusive man. my ex has went to jail last year for beating up his girl friend son and puting his hands on his girl friend and i brought this to the courts they still have done nothing please help me