I'm not going to share my Switch controllers and games
Why don't you want to share your controllers and games?
Well my friend is an aggressive guy, he holds the controllers too tight.
It's okay not to share with others if they don't respect your property. You should talk to him about his behavior so he can stop holding the controllers too tight.
This is gaming, people are going to get heated.
I understand that gaming can get competitive, but your friend needs to know he's being too aggressive.