What's Your Biggest Regret? - NYTimes.com - http://well.blogs.nytimes.com/2011...
"However, people whose regrets involved something they didn’t do or a missed opportunity were more likely to hold on to the regret over time. “The longer-ago regrets tend to focus on lost opportunities, things you could have done or should have done different,” said Dr. Roese. “More recent regrets tend to focus on things you did do that you wish you could take back.”" - Clare Dibble