I'm not opposed to doing science fiction or comedy, but there has to be respect. I refuse to be the joke, the fat woman joke, in any movie. I've turned down roles.
People can be cruel, but that doesn't mean you have to take it home, wrap yourself up in it and wear it.
It's really hard to go out knowing that you are going to be the center of attention just about anywhere you go and that it's not going to be in a positive way.