First of all, she was not in treatment, so her BPD behaviors were mostly unchecked

We got along really well and she seemed very deep and intelligent. I enjoyed the company and the closeness was nice because I hadn't been with anyone for a long time. The problem was mainly sexual. We had sex once, the second time we met. The third time we hung out, she told me that she had never had an orgasm with a man. I understood and we agreed to take it slow to see if getting comfortable would help things. I can't help but feel like she used this against me. She would repeatedly initiate and then stop sexy time. She even went as far as starting a blowjob before saying "I think I'm gonna stop her for tonight" 30 seconds later. I tried to please her, and she claims I got her close but I think this was a lie she told to keep me around. She then cheated on me, after I had spent 3 1/2 weeks being very understanding with her about her intimacy issues and not pushing her for any sort of sexual activity. She also gave me ecstasy the night she cheated one me in hopes that I would take the news better and not break up with her. She contacted me a few times (always from different numbers wtf?) and asked me to hang out. She would get mad and say mean things when I said no. I can't help but feel like she was just trying to humiliate me because she recognized that I was a lonely person without many other options. 

Any insight into her behavior?

Also, I'm afraid that she's stalking me online. 

What should I do if she is?

