What should I do about this girl?

There's this girl who went from really nice to complete ******. I really feel like it was my fault though causing this to happen. You see, I rejected her and now she hates me even after I apologized about it. When I tried being friendly towards her, she acted annoyed, and one day said this "Can't you take a hint I don't like you?" in which I replied, "what do you mean?" and then she said, "Look its best if we move on and you stop talking to me." Then I said "I'm sorry for any wrong doings I ever did towards you." She then told me its to complicated and to please just leave her alone. So I did. Well I noticed her that she kept on looking at me, and acting just really weird. One day I decided to confront her and apologize for the rejection. She told me I should pursue other women and that I need to understand I'm her problem and will always be her problem. When I told her that I don't like her that way, but that I felt bad for hurting her, she got really emotional and pissed and left. She turned around and said to our college security that I was really rude and hostile and even threatened her and this teacher (a fake witness) with a rock. They couldn't prove it, but then I talked to the dean and got a no contact order on her. Even to this bloody day, she continues to gawk at me when she runs into me, gives me weird looks, acts totally weird, and goes quiet near my presence... I just don't know what to do.