The helpful advice I received from the others was basically to move on, which I pretty much had done. I heeded their advice but modified it because we both worked together and I'd have to adjust accordingly without appearing to being an ass. Keep the peace so to speak. Thanks to some of your thoughts written here I was able to better understand her and define what was in my best interest.
The results were good for me. I stopped stressing over her and was able to redefine or better understand our boundaries. I basically retreated to the friendly coworker category. Although each encounter was friendly and uplifting to her, I wasn't the needy "Can I be in your fan club" guy she once dealt with. I stopped visiting her and left it up to her to maintain the relationship. Well, in her own mind, I don't think she was too satisfied because she made up reasons to visit me. This seemed to meet both our needs without the drama.
Okay, I mistakenly thought we could carry this forward a bit by just having lunch together. I invite her to lunch and as expected, she flakes. I didn't react, but I also made it known to her through my actions that what she did was unacceptable. She knew she screwed up. I altogether blew her off. For example, she would come join my group during a break and I wouldn't give her any special attention as expected. This seemed to have set the wheels in motion for her to go into an inner rage. Of which I've never seen the likes of. She was hunched over with a snarl and these piercing eyes. Like one of those gargoyles in the movies. It was pretty frightening but I've dealt with her being angry at me before. So, I didn't react at all. Treated her with a business as usual attitude.
She claimed she had a major fight with her bf, but what would that have to do with her taking it out on me? I mean, the only person she exhibited her anger to was myself. Through e-mails and and other methods, she was very condescending. I'm inclined to think she made up the fight with her bf story, and the real person she was fighting with inside her head was me. Let me explain, The issues her bf was upset over (including his reaction) were coincidentally things she had previously said specifically to me thru e-mail. My reaction was a carbon copy of his. What is going through this woman's head?

The only other significant reason she demonstrated this rage is because of my non-chalance to her possibly transferring to another position outside our office. She would fish for me to tell her not to go and how she would be missed dearly. I feel as though she thinks I'm in some way abandoning her.
She would seek my advice on the interview process and what to expect. We discussed the pros and cons of taking the job. It didn't make sense as to why she would leave considering she would be a grade level lower and her whole motivation in the first place is more money. I'm almost inclined to think she's not going anywhere and is making this all up.
The reason being. She shows up today saying she has a second interview and needs my advice. Again, I help her formulate her thoughts. But now I decide I'm going to play up the we'll miss you to the hilt role b ecause I suspect that's what she wants. Her reaction was unbelievable. She told me I was going to make her stay afterall. She wouldn't stop smiling and I couldn't get her way from my desk. She was like an infatuated child. In fact, she returned 10 minutes later with another item she received totally unrelated but I knew my cue was to provide her praise and reassurance. It worked. I had made her day.
Okay here's the thing. I think in some ways, I've become that parental male figure to her. Mainly because I've been steady with her brush aside her childish behavior and make her feel special. I show enormous respect and give her value. Is this the right approach or is there a better method where the BPD will be less defensive?
To a BPD, does it ever get too exhausting to participate in the push/pull pattern? To the point where you seek another person to initiate everything all over again? Thus, the reason for seeking another job?
Does a BPD write a script in their mind to be played out at a later date? It just seems she is manipulating things according to some kind of game plan. I've noticed, she has ever so slowly begun to expose herself to me. Whether it's pointing out her neighborhood, taking me to lunch in an area considered her territory or expressing some of her fears and insecurities. It's like she's really starting to trust me. Maybe in some way this correlates to her rage.
I just don't know.