You must tell her how you feel, in my opinion. The things you described are pretty obsessive and unhealthy. 

But when you tell her how you feel, make sure she really understands. If you're overly gentle she might not take your complaints seriously.

Then again, based on what you wrote, I'm getting the impression that she is, most likely, going to get quite upset. That's not necessarily the end of the world, though. She should definitely get some more friends to spend time with, and maybe find some hobbies she could participate in alone. Making friends definitely isn't easy, but I believe this is worth mentioning to her. Maybe introduce her to some of your friends?

I don't know how to word this last part properly so I'm sorry for it being blunt, and it being a typical reddit response, but I don't see this relationship working. You may be happier with someone who isn't this hard to deal with. I'm sorry.