I feel the need to cut out all contact with one of my best friends.
Why do you feel the need to do that?
He said he couldn't find much in common with me anymore.
I understand, but it's always a good idea to work on friendships if possible. You could regret not doing it later in life.
No I won't. I didn't know how fake he was. He won't like this and he better not contact me again.
I understand where you're coming from, but I still think it would be beneficial to talk with them about this. You may be able to work something out in the end.