RUMORS & REVENGE

Hi everyone. I heard a rumor about me giving a blowjob to a friend. When I told him, we went to talk to the girl that told it to a friend of mine (sorry for my bad English, it isn't my first language). At the end we went to his ex girlfriend and she told me that I'm a slut and a bad friend. I don't know what to do, this rumor is fake and she was a friend. Now I don't know what to do, I don't want to be her friend anymore after her words. Any revenge ideas? What should I do? I want to put her back in place.