I don't want to hang out with my best friend anymore
What's going on with your friend that makes you not want to hang out anymore?
I'm sick of his envy, whining and constant need for attention.
I'm assuming you don't care enough to talk this through with your friend, right? I'll support your choice either way.
It's just not worth it anymore.
Fair enough. I personally think it's for the better if you get rid of friendships that make you feel negatively.