I don't have any particular advice to give, but, assuming nothing improper happened here, if you gave it your best, there is nothing wrong with failure. Failure is part of the system. Your investors and employees realize that startups are a risky venture. There are plenty of jobs out there and your employees will land on their feet.

I have nothing but respect for startup founders who did their best and came up short. I hope that the experience you've gained serves you well throughout your career and one day you can look back and appreciate the experience. Good luck going forward.