I enjoy Twilight. But I'm not obsessed.
[Yes. I Enjoy the books, the movie was good. Yet I also love to Poke fun at the series. My avvie/sig is an example of that. xD]
I agree with Clouds. When you say they're ruining your life. It seems like an exaggeration.
Try to find something you have in common with them. When They start talking about Twilight, Just ignore them.