To say "Let it go and if it comes back, it's yours forever. If it doesn't, it was never meant to be yours in the first place" is to repeat one of the biggest cliches in dating.
Love and affection is something that needs to be reinforced, for some people more than others. When you don't reinforce and expect it to "come back" to you, you adopt the passive mindset rather than the active one. What if your girlfriend said 'if you loved me enough, come for me', and you also thought the same way, both of you would miss out on the opportunity of being together. Bummer. And it all started with a ridiculous mindset.
Out of most responses I agree with "NeedMyCoffee" and "ChrisCade" the most, you given the ball to her automatically be trying to control the whole thing. The words "you were an arse" were already written all over, so there shall be no need to repeat that. Trying to control the relationship only drive her away from you. Whinning and complaining and not sleeping will do you more bad than good. Assume the responsability for your mistakes and begin to do something about them.
Another thing, whoever this guy is, he is not doing this to hurt you. He doesn't even know you! While he is trying to actually get closer to her by being active, you're trying to get her back by complaining. Who do you think will get the girl at the end of it? The guy with self-dominance who goes after what he wants or the dude waiting for it to happen?