I had some free time after my morning class so I stayed around to hang out with a former colleague. As we sat and laughed, she said, "Let's not lose touch with each other." I told her that would never happen. We both agreed we are friends We care about each other and always will. We'll never be more than a phone call away.
Driving home I thought of all the other "friends" I've had that either retired long ago or are still at work. Most of the retired ones are long forgotten. Except for a few, the ones still at work don't miss me at all. We were never really friends, just people who worked in the same place, who bonded over the same issues. I don't mind and I am sure they don't either.
I'll reserve the word friend for those special people in my life. The others will be friendly acquaintances.