Help!!! Ex best friend vs boyfriend

My boyfriend made me stop talking to my best friend, because she was overall a bad influence for me and kept getting involved with the police. I told him all my secrets about her and things that he shouldn't know. She texted him saying that she knows we don't talk anymore but she wants to make sure he takes care of me. He blew up at her and called her rude names, and it was disgusting. What do I do?