You failed, it sucks and it wasn’t your fault.
Investors saw an opportunity the same way you saw one, that’s their game, its a numbers game for them. They invest in lots of promises, they win some, loose more but the wins cover the losses so don’t worry about them.
You did your best and that’s all that matters; the rest was beyond your control.
People fail like you every single day. In fact, almost every successful entrepreneur has a CV of failure much longer than you would have guessed, but no one ever talks about these failures; by the time they hit their big win, the failures are long forgotten.
Only the successes ever make it to TechCrunch and hardly anyone ever gets there on their first try.
So stop beating yourself up; get up, dust-off your shoulders and get to work on your next gig. When you reflect on this experience as you work on your next startup, you’ll be able to see just how much you’ve learnt from this failure and maybe even be able to appreciate it.
Keep tossing the coin and your win, your success, will come soon. You haven’t failed until you quit.
Best of luck.