My initial reaction when I read your Q was the (all too familiar) feeling of panic and doom. Yet, I pressed myself to read this post regardless, to see if I *could* help. That must be a positive sign for me, right?
I believe that writing the letter about how you are feeling about these deep, unhappy and hurt memories might bring you a sense of closure. LiteraryLark is so much better at explanations and descriptions than I am!