You were not the only one haunted by that “If only” but only a few can pass that landmark and be happy with "the now" whatever it may bring. It was never supposed that one man/woman should reach a certain life situation in which to live for the entire life. I guess change is part of nature and our human nature and by being satisfied with what "now" has to offer we create the future that will also satisfy us and make us happy. After all, it all happens "now" and this the only moment that we have.