Instead of dwelling on our regrets and failings (and thereby perpetuating our miseries), here's a suggestion to connect with the enduring influences of the things we did right: 

"The present moment is the dividing-line between progression and regression.  The present moment is the time when, by lapsing into laziness, even for an instant, you will experience constant suffering.  The present moment is the time when, by concentrating with singular intention, you will achieve constant happiness.  Concentrate your mind with a single-pointed intention.  Resolutely connect with the residual potency of your vitrtuous past actions."  —The Tibetan Book of the Dead, as translated by Gyurme Dorje (though overall we much prefer the older Evans-Wentz translation)