Yes, I agree with the other posters here. You have not supplied much information regarding her character traits, and what you have posted does not strike me as histrionic. How long have you known her? It would be a shame for you to miss out on a possibly good experience because you have mistakenly applied a disorder to someone.

Perhaps you may want to read more into the subject if you still feel that she is histrionic. Wikipedia supplies an article, as does this very site.