I'm no expert... But it seems to me that people join these forums every day, and post with the sole purpose of "getting that one girl".
Pick-up isn't really about that. It actually isn't solely about getting girls. It's about self-improvement. Improve yourself, and the women will come. All the of rules of PUA, and techniques are created to mold you into a more confident, alpha male.
Just my knowledge... You seem to have oneitis for this girl, and that isn't particularly a good thing.
Read these forums, learn, improve yourself. Focus on other girls in the meantime. In my experience, when you improve yourself, and start seeing other women, the women that you wanted before seem to show back up.
That's how it has happened for me and a few of my friends.
Hope i helped a little. And welcome to the forums!