I agree with what everyone here has said so far.

I can't emphasize enough to women when it comes to relationships (or just about anything really), if you get that fleeting thought from your gut that says "whoa....somethings not right" GO WITH IT AND GET AWAY ASAP!

We are so likely to rationalize what we are feeling, telling ourselves we have no reason to feel that way or wanting to give someone "a chance".

But, think of it this way....if it was meant to be, you wouldn't be getting that "gut" feeling that you can't really figure out....TRUST your instincts! Instincts do not lie to us!

I will tell you what I would do if I were in your friends' shoes right now. I would be changing my email address, changing my phone number(s), setting any facebook/my space/blogs to private, and informing everyone important in my life whether friends/family/employers/landlords/police that this person is over the top. I would save every email and records of his calls and what was said and when. They will provide the proof that this guy is not right.

I really wish your friend much luck and safety.