I like the idea of "needy cleanse", but if my theory is right, I don't want her to move on. She hates me now which is better than indeference IMO. But again do you think explaining things to her will work? If done in a non-needy way?
She has already unilaterally chosen to move on.
You have to accept that.
There are only two stages of breakups:
1. A man is emotionally-uncentered (needy, clingy, called mean names, acted beta, blew up her phone, kissed her ass, pleaser, etc) and the sex was just okay. Usually, in these cases the sex was only "okay" for the woman because in all aspects, the man was not dominant and a man who behaves like this does not have the experience to develop great bedroom skills. A woman will not dump a centered, fun, dominant male.
2. A man is dumped for being cold/distant, but the sex was great.
You can only get the girl back if the scenario is #2. And you do this by telling her your real feelings and showing vulnerability.
I hate to say this, but you are in the #1 category with this girl. you've already spilled your feelings to her, and blew up her phone with emotions. So the "I was too cold" part is way, long gone over man. You went from too cold to crazy, with no middle ground.
Your only hope is to live your life, and improve yourself to the point where if you happen to run into her again, she notices the tangible results.