The worst burnout/depression I've had from software development has been putting in years of time and effort only to have the project I'd been sweating on fail/

The worst burnout/depression I've had from software development has been putting in years of time and effort only to have the project I'd been sweating on fail/not be adopted/go under. This is across the board, from a Fortune 100 company that decided to axe a division to a well-financed startup that cratered to some of my own side projects I couldn't quite get out the door. It's just a gut punch to sit back and think: "If we'd done nothing we'd be in a better spot right now than this project that turned out to be a waste of time."