An empty platform holds evidence of departure mainly in the people who remain.

Departure shows most in what stays. The train is gone and the evidence of it is entirely in the people still standing there, in their faces and their slowness to turn around, which means leaving is registered by the ones who remain rather than by the one who left. Absence needs a witness.

If you are the one on the platform, let yourself stand there a moment before going back into the day. And if you are the one leaving, remember that the harder side is often the one that stays in the familiar place with something missing from it, and that a message on arrival matters more than it seems.