I've had dramatic changes in my thinking in all 3 areas. Religion... I've gone from confused Christian child to agnostic Christian (yes, there is such a thing). Gender issues... far too complicated to explain, but my views are progressive and liberal. Politics... I've made the trip from conservative republican to democrat, bordering on socialist. I try to be openminded, however, some of my views are set in stone at this point.

I hate to be cynical, but I have tried everything to help friends who are this insecure. The behavior you describe is evidence of some deep issues. If she doesn't recognize she needs help, and commit to counseling and hard work to overcome this insecurity, you are stuck with this behavior. No amount of reassurance from you is enough. Her fears and her imagination speak louder than your words or actions ever will.