How do I get rid of my "friend"?

My former friend "Angela" used to be nice and sweet. I told her all of my secrets, including everything my parents would murder me for. She turned mean and shallow quickly. She is super mean to my crush "Bob", and spits on him, insults him, and kicks him. She follows me around and tried to touch my and tickle my stomach, which I hate. She steals from me. She is nasty to everyone, and she said if I dumped her then she would tell my parents and her parents all of my secrets. My parents are very, very strict. Also, she insults me as well and tries to be popular all the time, even though she is a horrible person. She blames me for nobody liking her. How do I get rid of her?