This is not a good decision at all.

You're putting your life on hold for someone that had no interest in yours. It is selfless to the point where you are completely neglecting your own needs as a human being and putting her life above your own. You are putting her on a pedestal and eliminating your own self worth.

Sounds bad when I put it that way huh? But it's true and if you are willing to do this then it might be a good idea not to get into any relationships for a while and work on setting higher standards for yourself.

You got played. It happens sometimes. Now maybe it will be hard to move on but that is the only option. Sending an email like that tells her that it's ok to abuse you, lie to you and treat you as if you aren't important since you'll do whatever she tells you to do anyway. It tells her that you are still sprung... Regardless of her motivations it says that you'll be there if she needs a man to use and throw away.

You have to move on. You can't have a relationship with someone that mistreats you like that.