Custody agreement

My girlfriend is having problems with her ex complying with their custody agreement. If an order of contempt is filed against him, is he really in trouble? He is not following their agreement at all. Should she back off or try to get his visitation reduced? He is abusive verbally in front of the kids and mean in e-mails too. Does she have a valid complaint or will he get by with his actions? He seems to think he can do what he wants.