Hello all!
I have to also play devil's advocate here. I think that TRUE (ie: no backstabbing, lying, deception etc.) friendships are rare and hard to come by, so I wouldn't ever cut one of my friends loose because others perceived her to be a certain way.
I have a great friend who had a reputation on her because she was naive as a freshman and made a few poor choices. It never even occured to me to cut her loose. She'd always been there for me whenever I needed her. People were always shocked that we are such good friends because we were so different, but I carried myself in a way that people knew what I was about, and I'd like to think I could show the members of DEF what I was all about too.
Also, if we're worried about someone making us look bad, where do we draw the line? Would we stop being friends with someone unattractive because they might make you look ugly? Would we stop being friends with someone with a learning disability because they make us look dumb?