Getting Rid of Abusive Husband

How can a person get rid of an abusive husband who when you try to get him out of the home, he will start a fight with you out in the street, try to snatch your wig off and then when the police is called, he runs away and is gone by the time the police gets there. A restraining order of protection is already in place but the police are never there when you really need them. My friend won’t throw him out because she is afraid of having to fight in the streets or getting her son involved can get her son hurt. How would you handle this situation?