"Life can only be understood backwards; but it must be lived forwards."
We learn from our mistakes and we cherish our memories. That's how we grasp what life is all about. Situations can makes us smile and they can change us for the better. On the other hand, we can be bitter and anxious due to things that happen to us. There is nothing wrong with examining our past, as long as it doesn't keep us from moving on to better things.