From Scientific American:
The poem “Maud Muller” by John Greenleaf Whittier aptly ends with the line, “For of all sad words of tongue or pen, The saddest are these: ‘It might have been!’” What if you had gone for the risky investment that you later found out made someone else rich, or if you had had the guts to ask that certain someone to marry you? Certainly, we’ve all had instances in our lives where hindsight makes us regret not sticking our neck out a bit more. But new research suggests that when we are older these kinds of ‘if only!’ thoughts about the choices we made may not be so good for our mental health. One of the most important determinants of our emotional well being in our golden years might be whether we learn to stop worrying about what might have been.
In a new paper published in Science, researchers from the University Medical Center Hamburg-Eppendorf in Hamburg, Germany, report evidence from two experiments which suggest that one key to aging well might involve learning to let go of regrets about missed opportunities. Stafanie Brassen and her colleagues looked at how healthy young participants (mean age: 25.4 years), healthy older participants (65.8 years), and older participants who had developed depression for the first time later in life (65.6 years) dealt with regret, and found that the young and older depressed patients seemed to hold on to regrets about missed opportunities while the healthy older participants seemed to let them go.