How do you know she doesn't have OCD? It could be that it manifests itself in ways that you've not seen before. I have obsessive compulsive tendencies, but then most poeple wouldn't notice. Perhaps you'd like her not to "brag" about it, if that's how it seems... but are you really certain she's not suffering from this condition? You're saying she doesn't fit into your perception of OCD ... isn't that a form of stereotyping? What does someone suffering from OCD "seem" like? Are you sure that you're not the one with the narrow view of what OCD looks like? Just because you know a few people with OCD who aren't like your friend doesn't mean that you're suddenly an expert on the condition.

Even if she didn't have OCD, why would that matter to you? To be honest, how someone chooses to define themselves, or express their experience of life, shouldn't really get to you that much. Why should you WANT to persuade her she's not got OCD? Perhaps you could suggest she sees a therapist, and let them decide what the problem is (if there is one.)

I hope you're not cross with me, I'm not trying to be snotty or anything... just I really can't see why this is such a big deal to you.