DON'T TOUCH MY HUSBANDS BEARD

A friend of mine (husbands long time friends girlfriend) hates my husbands beard. She will voice it as soon as she sees him and makes fun of him. I have told her nicely several times to stop. This past weekend, she was drunk, walked up to him, grabbed his beard and yanked it saying "I hate it!". I wasn't there but he told her to stop and she said "I'll stop when you cut it." He told me not to start any problems with her, but honestly I feel like I need to grab her by her hair, yank it, and say "DON'T TOUCH MY HUSBANDS BEARD!" Would you do something or leave it be? Remember, I have told her nicely SEVERAL times to stop, so the nice route doesn't work.