Coworker difamation

Coworker difamation: I've been working for about a year now in a new job I found, a new coworker was hired and she have been stating rude and insulting words towards my family and my wife too. As example: a few days ago I was talking with a coworker about how bad I feel because of the flue simptoms, pain in my back sore throat and fever then out of the blue she starts yelling that I got herpes that most likely my wife gave it to me . . . In front of the rest of the others coworkers. Also in the past while talking with my coworkers about spontaneous stupid and funny situations at the same time, how we would go over those situation she will compared the stupidity of the situation with my mother, which she doesn't even knows, and of course in front of the others coworkers also . . . ! I feel so bad now because my coworkers have in mind that idea of my mother being a stupid and my wife being sick with herpes, myself knowing that she is no doctor or spyquiatrist to make those statements . . . What can I do to protect myself from these agraviations and difamations false statements. Should I have take my job to court for not having this situation stop, or take her to court and have her a restriction order against her . . . ?! Thank you . . .