It was once said to me, that a good way to get rid of pain and hurt caused by someone (or at least a good start to getting rid of it) is to write a letter or poem to the one who caused the grief. Explaining in detail how you feel, how they made you feel and adding everything you ever wanted to tell them, though the intention is never to give the letter or poem to it's recipient, either a blog or burning it, usually helps.
I have to admit, I have used it and just feeling as if I got it out did help.
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