If only she knew the hoops you are jumping through to be her "best friend". I think she made it pretty clear that she didn't feel that way for you when she broke up with you and to be honest, she was losing her feelings long before that. You can't help how you feel and while it may be 100 percent held up on your end, it takes two for a relationship to work. I know you rather have her as a friend than absolutely nothing at all, and it's pretty obvious you hold her in very high esteem (on a pedestal if you will) but as the other two have said, you have to put yourself first. Being her friend is not allowing you to be happy with anybody else. You don't even have the feeling or the gusto to put anything in with anybody else. You are also feeding her ego by confessing to her all the time that you still love her while she chases other guys and does her own thing. If getting her back is what you wanted, you aren't getting any closer.
Like they said, you have to remove her from your life so you can let the healing begin on your end. 2 months is not nearly enough time to get over a first love, a best friend, an everything. I'm on six months on my own and I'm still woozy at times. It's very frightening and extremely difficult to let her go but you have to for your own good. The healing can begin and you can find your "macho" side, and your confidence again. Or at least get some practice in with dating because dating somebody since you were 14 really put you behind the 8 ball in terms of experience.
It has to be difficult to not get ANY interest from anybody but as you mentioned, you couldn't even give enough effort anyway. Start today and let her go, and if she wants to contact you, tell her that it would be better if she didn't. If she knows how you feel, she should understand. It might even make her miss you believe it or not but it won't bring back any feelings again. This is where you start, and you make the progress by doing what you can to cheer yourself up (fun things you like to do, get yourself in better shape (sports club/team, gym, running, etc.) and build yourself up. What she does with her one night stands is not your concern anymore because regardless of how you feel or what you think, she is going to do what she wants. And that is what she wants to do. Don't put yourself through any more torture.
Everything will be alright and you will be able to meet plenty of new people and make many of new friends without her in your life. Friends are supposed to enrich your life and make you better off with their influence, and I don't think she is doing that for you, is she?
Waking up next to a beautiful girl,
Step outside and say hello to my beautiful world.