Bad friend ?

I know this guy he bullied me for sometime and I confronted him and I told him to stay away. My best friend still chooses to hang out with him after all the bad things he’s done to me. This hurts my feelings because she is my best friend, isn’t she supposed to take a stand for me? when I told her about how I feel uncomfortable around him she said that she is not going to stop being friends with him because she thinks he is a nice person. Am I wrong to feel this way? I don’t want her to be friends with him.