I'm glad that you are feeling really good about yourself, but I don't understand what you are trying to accomplish here.
From what I gather, you want to look your best to impress her by doing these super intense workouts. All of this seems to be a ploy to win her back and to show her what she had let go.
Now, you said that you are starting to have feelings of hate, because of the way she cold-heartedly left you. If this is true, why do you want to get back with her? Do you really want to get back with someone who hurt you? Or maybe, your love for her has turned to lust.
My advice to you -- stop this ploy bulls**t and try this new woman that wants to go to dinner with you. Forget the ex!