Ok to folow up:
If you are the weaker nice guy, and most guys that are in this category don't know it, stop being an unconditional pleaser.
There all kinds of books and web sites dedicated to the art of flirting. Which is definitely an art. If you can flirt and make a girl laugh that you barely know, you are ten miles ahead of the game. LEarn to flirt well.
You don't have to be an asshole, you just have to come across as a dating prospect. As ZTAngel said, maintain a certain aura of . . . something. It can be a positive aura
People are the way they are, bemoaning fate doesn't change it. Personality is very changeable, its a method of comminication we develop at the earliest ages to get the world to like us. However, it is still just a method of cumminication, so if it isn't always getting you what you think you need, then work on it and change it a bit.
PKTSU01 is right in his analysis, many women seem to want a relationship to fulfill them on multiple levels. One of those levels is drama or excitement. If you know this you can create little things for good drama and spare yourself fights for the sake of excitement(conflict) and make-up sex (redemption). If they aren't already stuck in that pattern.
As far as the little filly you mentioned, well did you ever think she might feel a little rejected? I mean its a pretty positive indicator of like to have a girl on your couch in various states of being disrobed ask you "want to try sex?". If you need a sign clearer than that you need to be hit in the face with a bat.
That also assumes she didn't come out of the blue with the comment and that you had gotten her thinking about that moment. Meaning you went pretty far with her sexually, like say third base. For those of you that are baseball/sex metaphor handicapped, that means the boy went south of the belly button.
As far as her playing hard to get now, or playing it cool, most people I know that are doing that are really having self esteem/self image issues.
Hasn't there ever been a time of day that you weren't feeling good about yourself, the way you look or feel? You don't really want to have a prolonged encounter with someone you are crushing on at those times. Most of the time people blow by us it has nothing to do with us, its something going wierd in their head.
And as for her, well she made an adult decision as an adult, and you sent her packing naked from your couch like a school girl you suddenly realized was under age. And you didn't have some committed relationship going where you could give her the "I want to definitely wait for something corny before we do it" line. She's not a mind reader and will likely read more into your words than you intended.
It sounds you are thinking more than you are acting. A simple way to find out if she is still interesting is to pick up the phone, dial 7-digits, and ask her to go get some dinner with you. Boyfriend girlfriend stuff.
I'm rambling because I am hungry so that is enough from me
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