Sometimes people pass in and out of your life in the blink of eye, yet in that instant you are indelibly stamped. For a breath in your life the two of you are exactly the people each of you need. Then you exhale and your respective lives continue on their own paths.
A few years later the two of you reconnect. Your lives have gone in different directions but you both still look back fondly on the moment you shared. Not out of any desire to relive the moment, merely a recognition of the positive impact your shared moment had on your respective lives and how that moment has positively shaped your life since then. You're happy for one another.
With the passage of time you come to associate one another with a particular period in your life. You never forget your first experiences, whether good or bad. However when those firsts were positive ones nostalgia is a much finer spirit, like a fine Scotch. With every sip you remember the music that was popular, the experiences you were having, and even how you were feeling.
Before you entered one another's lives things seemed muted. The clouds were still black. You hadn't yet discovered their silver linings. You were lonely, you were frustrated, and you were full of self-doubt. The two of you started talking online in those early days of the Internet. You made each other laugh and smile and you found your way into one another's hearts. The clouds had cleared and your life had gone from muted to amplified. And you get all of that from just one sip of Glennostalgia Scotch.
So twenty years later. You look back with the gift of hindsight and realize what a turning point you were in one another's lives, how much your shared moment guided and shaped you in the years since. The two of you haven't been at best Facebook voyeurs of one another's lives since reconnecting. Happy for one another's joys and empathetic for some of the rough spots but content with the convenience of the acquaintance provided.
Then one day there's only one of you. Life goes on. You have your friends, family, joys, and your troubles. And yet, where there once was another there's still family, friends, and twenty years of life experiences now it's just memories. You see the sadness of those friends and family that have been left behind. You feel for them, you grieve for their loss. But as a mere voyeur in the other's life, you feel guilty grieving, as if you're stealing from those who were much more a part of that life, of those twenty years since your lives diverged and traveled different paths.
So as you look on from afar, you raise your glass in thanks and respect for your shared moment in time and for the lives you've lived since then. You bow and walk away.