Hello Ben,
I know it bothers you to hear people say that 'she wants to have sex,' and I can see that you're implying that she said she didn't want to BUT these signs she's giving you can only mean one thing... I know she told you she wants to save herself for marriage and that she wasn't willing to go that far but at your/her age, her hormones are going to tell her otherwise.
I believe both theories are true. She DOES want to save herself for marriage, but at the same time, she's getting these sexual feelings/urges that go against these values. It's PERFECTLY normal at her age, and I've seen it happen a few times before. If I were you, I'd stay away from this no matter how great the urge to try it is, in order to avoid any regrets.
Good luck
, Carpe Diem.
PS. You really should listen to what these people are telling you, the signs she's giving are pretty obvious.
PSS. Sorry! Didn't realize it said 'female advice preferred!'