If you’re setting out, seeking publication, you've probably figured out that at some point you’ll be disappointed, sometimes devastated, and often there’s nothing you could have done to prevent what happened form happening. Don't focus on that. Focus on what you can do; what is within your control. Let the fates decide the rest.
My advice if you've taken one of this major hits is to take a play out of the Seahawk's playbook for next year. Do you think they're going to just roll over on this? They'll be back. Fighting harder. Recognizing their mistakes, and bettering themselves to get there again. They'll also take an honest look at themselves and figure out what they aren't and what they are good at. I think every writer should do this. It's how you learn to write like you and not try to write like someone else. In other words, don't try to be a passing team on the one yard line when you're outstanding at running the ball.
Many of my friends that had the publishing bomb detonate in their face this year did the same. Do they all have new book deals? No. But I know where I'd place my money on them getting one soon.