Recently one of my friends attacked my image by telling a lot of my other friends that I did something (that i did not do). A couple went along with it, causing other people to actually believe it and look at me with disgust.

If I playfully go along with it (agree and amplify?), it will appear that I'm admitting to it.

If I deny it, it'll seem that I did it and am desperately trying to deny it.

If I confront him about it he'll say something like "It was just a joke, I didn't mean it" and I'll appear weak because a "joke" got me so upset.

What do I do?