Farewells are rarely equal in the futures they ask each person to enter.

A goodbye looks symmetrical and almost never is. One person walks into a new set of rooms and new problems that will occupy them from the first hour; the other returns to the same place with a gap in it. Both are sad, but the sadness has different work to do, and the one who stays usually feels it longer because nothing else arrives to fill the space. Neither chose the imbalance.

Whoever is leaving should keep contact going a little past the point where it feels necessary. If you are the one staying, say what you need rather than waiting to be missed.