One of the many things that's difficult as you grow older is the realization that you can never really "go back" to what your memories are of a time that may not have been as "perfect" as we recall. That and the fact that life is constantly changing and doing so at what seems like an exponential faster rate. And of course as population grows (even though our "rate" of growth may be trending down) that only exasperates these issues. IMO being able to "accept" this is one key to having a satisfying and happy life. Being unable to accept is a one way trip to depression and unhappiness. Moreover, the latter is a key component of why there is such polarization in our political views today. All of course, IMO.