If you’ve have had a number of jobs in your life, you’ll understand that, although some of those friendships you developed at prior workplaces may linger, if you don’t share some fundamental feature of human understanding — they’ll probably fade.

The same goes for neighbors you’ve had as you’ve moved your body around the world. As well as friendships you’ve had in high school or college. People come and go in your life, some last a day, some a year and some much longer.

Perhaps the hardest part of friendship is letting go.

I had a dear friend in high school. My only friend in high school, really. We played hookie together, were on the same sports team (rifle team) and worked the same strange summer job our 17th and 18th years (running a blueberry farm in Frankford, Delaware). We went our separate ways our last September and lost touch but for a faint spiderweb tendril that joined us and wavered in the wind every so often. Strangely, we got married the same calendar day, and married a woman of the same name, all unbeknownst to each other.

He committed suicide a few years ago. I have never learned why he didn’t bother to say goodbye. I would have understood.

We ride this train and people step on and off our personal Pullman car. Yet in the end we pull into the station alone. Waving goodbye, along the way, to those who have ridden with us through the rough spots, the early track, the long lonely stretches — is hard.

But you get used to it and learn that people come and go. And that is just the way of it.

Friendships melt like winter snow and are followed by blossom-like faces of new acquaintances, who, if you’re lucky, may sing to you songs of the fresh season.