I'm going to cut a close friend off
Why cut him off?
I feel he's not worth hanging out with anymore
I get your point but it's not nice to stop talking to people who really care about you. You should try and work out your differences.
You don't know what that guy did, he's a turd. It is just not going to work out.
You became friends for a reason and cutting them of can be hurtful. You shouldn't just stop talking to him. If you don't want to be friends anymore it is better to talk and end your friendship in good terms.