Typically, if someone hates something I like, I just don't give a shit and move on. Pretty much the only time it actually gets to me is when it's obvious that they're just parroting what they've heard other people say, and don't actually know what the fuck they're talking about. I still usually won't dignify that kind of bullshit with a response, but it's fucking irritating.
It's like, you're allowed to dislike something, but at least have an informed opinion and know what the hell you're talking about if you're going to go on and on about it.