One thing keeps coming into my mind these days...one of Guruji's (Paramhansa Yogananda's) sayings:
"Live the present moment supremely well, it will whitewash the dark past and compel the future to be bright"
I too feel very strongly that this alone is the thing in our hands...in fact all that we do to calm our mind, to keep ourselves healthy, is just to enhance our performance in the "NOW".
I often used to dwell on "what I should have done in a certain situation"...but no more....
It is not that important. If we need any reference from our past experiences, we may just flip thru it and that's all that is required. Every moment is unique....full of untapped potential..if we could just keep our minds open...without any bias...ready to embrace whatever life offers , it will be a joyous experience all through..free of resistance.