Your descriptions of your experiences in this relationship are incredibly similar to things I've experienced . . . It's kinda scary. Since you're interested in understanding motives, and are confused by seemingly contradictory reactions, I'll share some bits of my story which might help shed some light.
My relationship lasted nearly five years (3 years in college, then 2 years long distance in grad school) before breaking down in terrible ways. In reality, it started breaking down shortly into the long distance part, but it is way too easy to simply believe it is just the distance causing problems. Anyway after an extended period of craziness between us (there were a solid 3 months where she would break up with me at least once a week in the evening, then pretend it never happened the next day) I finally told her that the next time she broke up with me I was going to believe her and take it seriously. It was nearly a month after it was all over that she finally started to realize that I wasn't just giving her the silent treatment. . . .
That story makes her sound a crazy person, but the reality was simply that we had entered an unhealthy cycle that was building on itself. The chaos she was bringing into my world was destroying me, and caused me to withdraw to protect myself . . . which in turn caused her to lash out at me in hopes of getting a reaction from me that would show her that I cared. Everyone around me would tell me that I always looked tired and sad whenever she was visiting me.
Even now, years later, I still recognize everything about her that I liked, and care about her deeply. In the occasional interactions that we have, it's almost like we're able to just pick it back up where we left off. I'm too easily drawn back into her personality when we're talking. . . it isn't until afterwards that I'm able think clearly and realize how dangerous those interactions could be.
She has made several attempts to win me back . . . she'll go on two month long stints of being on her best behavior, but eventually gets frustrated that it isn't working fast enough. The reality is that I'm well aware of her game.
Jazzing up the sex appeal and confidence will definitely catch attention, and might seem to make you feel like you're getting back on track, but in reality it'll probably be seen for what it is. Odds are that the harder you push, the more cautious he'll be of you. The real thing to do is to develop consistency/stability within your life, and he might begin to notice that in a positive way . . . but the key point is that you need to be doing that for yourself, and you also have to think carefully if you're able to focus on yourself while he is around.
I hope things settle down for you and you're able to find peace with the situation.
B
