Well,
everyone has "something" wrong with them. That's probably something to make clear to her, because nobody is perfect. Would she consider herself a "freak" if she got migraines all the time? Probably not. What's the difference between that and having OCD? It's just a disease. Everyone has 'em, no one cares, you know?
I guess I'd just listen to her and try to tell her to look on the bright side about things. I'm sure if she confides in you, you're smart enough to turn around what she said. I wouldn't be forceful with it. I dunno, I guess I don't know this girl, but it's probably impossibly to completely change her mind, but if you point out the good in things, listen to her complain to you, and as she gets older, I think she'll be completely okay with things -- soon enough.
[a little off-topic in this paragraph] But yeah, there's nothing particularly freakish about it. In fact, some guys probably find it attractive. I know I do. Haha. Every girl I've ever been with has had some severe mental problems (and, no, I'm not being misoginystic -- "oh, girls are all crazy!", etc ... they genuinely all had some psychotic issues they had to get medicine/psychological help for), and I dunno. I find it kinda sexy. Crazy-sex rules.
