Annoying friend please help!?

I think it is best to be straight with her. Have a talk and mention to her that she may not realize it, but that she is continually talking about her height and that is it becoming annoying. A friend deserves to know why their friend doesn't want to be friends anymore. Walking away and ending the friendship without letting her know the real reason is not the answer and is not fair to either one of you. Good luck. I hope she listens to your concerns and is able to stop talking so much about her height.