Hello. I'm 21 years old. There's a 27 year old chick from my studies that I befriended. We study together, been to places, had drinks etc'. She's slept at my place a couple of times, each of which involved some light sexual playing - mostly touching, and I jacked her off once. But she is always avoiding anything more than that, last time she let me touch her but not kiss her, the claim is that I'm too young for her and that she's used to dating guys over 35. Likes them rusty I guess

Now obviously she's attracted to me, otherwise there would've been any kind of a sexual contact.
I told her that I understand that she's used to old men (this is all half-humorously - I don't actually think 35 years is old lol) but I don't care for it since I have the maturity and mentality of a 35 year old - with the body of a young man. I said that I know that she likes to play these games just for entertainment but if she doesn't plan on anything happening it better stop altogether (many times she initiated the contact, e.g puts her leg between mine when we lay in bed and watch TV and stuff). She said fine but had a hard time complying.
I'm pretty sure she's just dilemma'ed since she's basically looking for a connection that's good enough for marriage (she lived with and almost married with 3 guys in the past) and although I'd be fine with getting serious with her- marriage is off the table for the next 5 years. So she's probably not sure of her willingness to get involved due to these circumstances.
What I assume is that the right thing to do is to let it cool off and be a bit cold, yet still friendly to her. And to show no sexual compliance if she tries anything. Am I missing something? Is there something else? What about just going out with her for a beer?
Thanks.