Similar thing happened with me and Michael Jackson's music. I was on an irc channel when someone mentioned one of his songs and I agreed. One of my closer friends said, "you know he's a pedo, right?"
And I started thinking of the kids Michael had sharing his bed and realized that, until then, I had had sympathy for them only in an abstract. Now I think about those kids whenever one of his songs comes on, and you know, I no longer enjoy listening to it.