You did the work and nobody showed. Stomp your foot, make the angry call, swear “Never again.”
Then remember the work you did and the time you spent doing it. Remember what you learned. Remember the improvements you made and the clarity you achieved. Remember that just because nobody wants the thing you made today doesn’t mean they never will; you have a product in your pocket now. Who knows when it will come in handy?
Remember that work is a gift and its own reward, and that if it’s Deep Work then that’s true in spades. Maybe nobody wants it today, but nobody’s taking it away from you, either. You’re still free to do with it what you will, even if that means giving it away to see what might happen.