Rebecca Solnit has some great things to say here:
"So, what do we do when the world is ending? The same things that so many of the giants on whose shoulders we stand did when their worlds were ending. We choose to face our despair—to walk toward it and through it—choose to take action, choose to build movements. We do it because we don't know how it ends, because there are possibilities out there that we simply can't see from here."