Is my stepmom hinting that she wants to sleep with me or is she just playing mind games?

I don't know how many of you guys follow my posts. I could most certainly forgive someone for thinking that I'm making this stuff up. Anyway, my parents divorced in 1998 due to a) a loveless foundation for a marriage and b) emotional abuse and adultery. My Dad was having an affair with a woman who worked for him. They have been together now for 19 years. What follows is a brutally honest dynamic between me and my stepmother:
I am a self admitted malignant narcissist. I agree with the contention from my shrink that there is a biopsychosocial basis for this. That is, my personality is a result of my genetics, biology, environment, and society in general. My stepmom and I (lets call her S) were never close. It was often a cold relationship. She got a long with the other ones. Just not me. In hindsight, I'm amazed at how much she could always deduce about me. During puberty, I was extremely sexually attracted to her (still am). I used to go into my Dads bedroom and I would take her panties and smell them and masturbate with them etc. I'm 24 and still living at home (moving away this summer). Last summer S asked me if I could take out the garbage to the dumpster at our house. On the pile of garbage was a letter. The letter was even dated 1998. It was a love letter my Dad wrote her. In the letter, he said that he hated being with my Mom and that he loved her and his children. It was obviously a very intimate thing for him to have written for her. A couple of weeks later I was home for work (11PM, same time everyday) and she was standing there in the kitchen wearing nothing but a very small t shirt. She was organizing the fridge very loudly. I know 100% that she knew I was looking at her as she did this. The next morning I got up and she was sitting on the couch watching TV. She looked at me, smirked, and said "hi" softly. That summer I left to live in a nother city for a bit. As I left, she smiled at me and gave me a really big hug, pressing her breasts against my chest. She then said uncharacteristically "you're going to have so much fun". I couldn't find employment there, didn't have much of a plan, and moved back home. She has been rather cold to me since I've been home. I think she is nwBPD/nwHPD because of her emotional shifts, coldness, vivaciousness etc.

A couple of nights ago I came home from work and didn't go downstairs. The reason I didn't was because I felt like sitting in the living room on my cell phone. The stairs are loud and you can tell when someone walks down them. Anyway, as I sat in the chair, S came out of the bedroom wearning nothing but that t shirt she wore before. This time she turned on the lights, paced around the kitchen a bit, and lifted her torso which exposed her wearing a pair of black panties. She then went back to bed. Ever since she has been completely cold to me and when I pass her she doesn't even look at me. She is giving me the silent treatment.



Do you think that all of these aforementioned factors have been clues she has been leaving me to have an affair with her? Or do you think that she knows that all of these things are messing with my mind? Do you think the sudden silent treatment and lack of sociability is indicative of borderline personality disorder?