How can I help my friend?

This guy we call Cabagge Guy (cause his last name is McCabbage) was spreading around this rumor that him and my friend bre were dating. She talked to all the teachers about it and even the ones that she didn't feel comfortable around. Her and Megan went to the counselor at the school and they talked for almost a whole class period. It's really taken a toll on her and she can't concentrate andstuff. How can I help her feel better and get over it?