Most people, I imagine, don't really know what they should be regretting. For instance, it is possible one could regret not keeping up with old friends, while i

Most people, I imagine, don't really know what they should be regretting. For instance, it is possible one could regret not keeping up with old friends, while in reality it would have been a detriment to happiness. Humans are known to look at the past with rose colored glasses.