How to stop being friends with someone?

I have known this friend since 1st grade and have been friends with her since 5th grade. We became basically best friends in 7th grade. That same year though (7th grade) she told a secret of mine I told her not to tell anyone. Our freshmen year I trusted her enough to tell her a secret again and she blabbed that one as well. I am now coming to the realization that she isn't a very good friend. And she is very awkward. She won't talk to people at all. And even when I talk to her it's hard to keep a conversation going unless it is just us two talking. We also have different views on life. I am sick of being her friend and realize that I don't need her in my life because she is just bringing me down. What do I do?