I didn't receive any response on my last post but I'm posting here again anyways. I need to be heard and I need help. Please see me.

My boyfriend thinks I'm being irrational and immature for avoiding my best friend. He's siding with him. He constantly wants to talk about him and what happened. He keeps telling me how wrong I am to hate my best friend over what happened. He's trying to convince me to speak to him. 

I don't want to. I hate this person more than anyone I have ever hated. I don't want to be involved with him ever again. 

But my boyfriend thinks I'm being a child. 

My best friend crossed a line by telling my boyfriend how I was feeling.

Why can't I hate this person? Why is everyone siding with him? I feel like he's playing the victim. If he didn't wanna be hated by me, he shouldn't have gone behind my back.