Hello, this is my first post so I apologize if its a little wanky.
A few months ago I started talking to this girl online again that I used to go to school with. I always had a crush on her but she had a boyfriend at the time. So we meet for coffee one afternoon and had a great time. We're talking later that week and she invites me to her town, 1.5 hours away, to hang out and spend the night. After a night of just hanging out I make my move when were in her living room. 30 seconds later were kissing, 5 minutes later were naked in her bed making love. Now I already know I shouldn't have waited till the end of the night but things still worked out the best they could have. The next day she drops me off at the bus station, we kiss goodbye and I go home. We never really talked about any of our intimate details. We jabber on and off for the next few weeks.
Now this is a girl I would like to date. I don't pursue it at the time because I wasn't satisfied with my current lifestyle even though she was already aware of it. I kinda talked myself into the idea that I wasn't good enough to be her boyfriend currently.
So a little more time goes by, talking isn't as frequent, and I ask her if she wants to get dinner for valentines day. I get the bombshell thats shes dating this other guy now.

So now I'm kicking my own ass for being so, so, I don't even have a good enough adjective for it...
So I humbly ask any advice. I don't know her boyfriend and don't care to. I feel no 'bro-code' for someone I've never met. I'm racking my brain when all I think is that opportunity knocked and I slammed the door in its face.