Statistically speaking, most of us don’t get to say goodbye. In either direction. So as a mitigating factor we sacrifice experience, push away maintain an odd pathology of loneliness.
Or we humanize things as a coping mechanism for The End. You’ll tell yourself with full certainty how much your cat must miss you, in order to avoid the primal, animalistic understanding that we will all one day go suddenly and without warning.
Along the way a few things will slip into your consciousness. Much like how your uncle brought back shivers from the war, but left the rest at the Front.
You'll visit the same smoke shop every other day. greet the same counter girl, joke how the energy drinks you buy will do more damage to your body than anything else in the store. Notice her new piercings and tattooed freckles, walk out promising you’ll see them tomorrow with smirk. Then one day you'll move away and never think to say farewell.
Or find the shop closed up after spending a week out of town. Nothing left save for a few garbage cans and empty boxes on the other side of the open sign.
The more you look at them, the more they start taking on a human form, an identity like they’d been kicked shoved punched in the gut cast aside until a city worker calls to have them disposed of by the department who handles such things.