I know how you feel. I'm very oneitis prone myself, even now when I'm older and should know better. The best advice I can give you is to use this drive you have for this girl to better yourself. If you wanna have even a remote shot with this girl you have to become a man with options. Options are really sexy, a man with options sends a message.
So you used your drive to get in shape, that's awesome, you look great, you feel great, you're a natural with girls. You need to use that to game other women even if you're not serious about them. She needs to see you sexually, she needs to see you with other women. This also has the advantage that you'll be thinking less about her. There are some girls that you fall in love with and feel like you could love them forever, but still, when you're seeing other women, it is easier not to think about them all the time and to have your head straight when the opportunity arises to make a move with this one special girl. It's also easier on you when it hits you she's with someone else and doesn't want you. Because those moments happen sooner or later, which doesn't mean you'll give up, it just hits you and your ego that you don't have her.
I have a slight oneitis as well. The girl has a boyfriend, but that doesn't stop me from being touchy, playful and flirty with her. When I fell in love with this girl over a year ago, I was so smitten by her beauty that I had a diarrhea every time before I was going to meet her. I don't have to tell you that I couldn't really be my charming self around her. So we started hanging out, I was really afraid to kino or anything else, I had to mental slap myself just to behave normally around her. I found out she had a BF, ok, fuck it, it won't stop me. She's still with him, but I'll be here when they break up, that's for sure. We became good friends, and even though she confides in me, we have long talks and all that stuff, I try my best to stay away from the friend zone. From the weird beginning and to where I am now, the one thing that really opened my eyes was 60 years of challenge. When I read his stuff I realized I need to start sending the sexual vibe before it's too late. So that's what I did. Now we cuddle, I grab her ass, take her hand and put it on my p***y and she is sometimes bewildered by this behaviour, but doesn't really mind it. Nowadays I can send her a message to tell her I wanna see her, that I've missed her a lot, but mostly I just wanna feel her out and squeeze her booty
I don't know if this will get me out of the friend zone, but I'm not gonna give up. But the key to all of this was that I started seeing other women, having sex with other women, and being less available to her. I'm not gonna jump at the first suggestion to meet with her. I just don't see her that often, but when I do, I make it sexually charged, fun, flirty, naughty and sometimes deep, like singing her my songs and shit like that. And I'm not afraid of saying the wrong thing, or offending her. If she reacts badly to something I do, I just brush it off, or turn the joke on her. If you don't acknowledge it, it didn't happen.
So, to conclude this long post (I'm waiting for a football game to start so I don't mind spilling my heart out here
) use the drive to better yourself, stop making her the centre of your life, stop being afraid of losing her (you can't lose what you never had), create a sexual vibe between the two of you, be rude, be inconsiderate, be a bad boy, be sexy! And the last thing, you have to change the way you think about her - so next time you're thinking about her, fantasizing about your perfect life together etc., don't focus on the feeling of lack, don't focus on the fact that she's not yours, just focus on her beauty, her presence, on everything that is wonderful about her. When you think like that, it's pure desire with no fear of loss or of not attaining. That's a good frame of mind to be in! Most of all, always love yourself more!
Hope this helped,
cheers mate!
CHAT