In retrospect, I don't think I'd change a thing. Like so many who make it into their seventies I can look back on a full life. Like most, I've had my moments of 'agony and ectasy,' my boredom and fascination with what has been going on. I like to think all of it has made me grow inside as a human being. Without the harshness of some lessons I would not have learned many of the things I know now.
I've long believed that we come into this world of 'relativity' in order to experience. That experience covers a wide spectrum. We have our dreams, our desires, our likes and dislikes. We compare all the time what we think or feel we'd like with what we've got and try to change the outside world, generally to realize later in life that the world outside changes (in the way we interpret it) only when we change inside. And certainly this is not the sort of insight I'd have had at twenty, or thirty.
No, I've had - and am still having - a full and interesting life and, to reiterate, I wouldn't change a thing.