i found that looking at my past helped me to learn how to change my "now", my perspective. it didn't change the past tho. it opened up my mind to what i could learn from it and then move on to today. i did this with my T. we didn't dwell on those painful times so much as to help me retrain my mind to positive behaviors and beliefs. i threw out many false tapes and slowly replaced them with new ones. real tapes, if you will, rather than many false beliefs i had about myself. i still have to watch carefully for triggers that set my mindset screwy but my therapy gave me many good tools to work with.
hope this helps.