He wants you to be with him every second. He wants
you to do only what he thinks is right. He wants
you to be like him. And, nothing you do will be
enough for him as long as you have an independent thought
in your head.
You're in a tough spot. If you lay down the law
and demand some independence, he's going to squeeze
even harder. (Go ahead and try it, I bet that's what
he'll do.)
Without any big declarations, you need to do more things
on your own. Your friends probably miss seeing
you around and would enjoy getting together.
If he is a reasonable person, he will see that your
independence is no threat to him. If he can't
deal with it, you might want to find someone who is
more secure.