How do you handle a mother who hates your husband?

Your mother is acting like a child. I would completely cut off all ties with her. Nothing says your mother has to like your husband. However, she does need to treat him with respect and act in an adult manner. I have gone 3 years without talking once to my mother because she was acting the same way. She finally realized if she wanted me in her life she would have to grow up and act in an appropriate manner. It hurt not having my mother in my life but it was well worth not having the drama anymore. If she calls DCF and you have nothing to hide, there is nothing to worry about. She however can get in trouble for making false claims.