Open Question: Histrionic Personality Disorder - knowing someone with this?

I know, or perhaps *knew* is a more suitable use of the verb now, a woman who I think has histrionic personality disorder. I am not one to classify and pigeonhole folk, but she really does seem to be a perfect example of it. I thought we were friends, but she seems to have just used me for her own sense of vanity, being inappropriately flirtatious, caring over-the-top about how she looks, making a crisis out of nothing, and pretty much being too flirty without maybe really wanting to take anything further. She's been brought up in a very traditional, conservative family in Taiwan - she is 28, so not that young, but she cannot be criticised, or told anything she does not like, without getting angry. Ironically I really began to fall for her when I began to understand her better, after spending time with her in her country this year, but she really does seem to use people - i.e. guys. We are not exactly friends anymore, but is it ever worth pursuing friendships or relationships with people like this, and how do you get through to them, without flattering their vanity? Monty