Be flexible. Your determination, focus, and drive allowed you to power through on a project that you are now recognizing in hindsight might not have been the best option. Changing targets isn’t quitting, it’s counter-attacking.
You are only 30. So many opportunities to keep swinging. All it takes is one hit. Be adaptable. Let yourself recharge. Figure out how you can take more swings in shorter periods of time. Figure out how each swing can work together to push you further towards your goal. As much as your work seems a failure now, there is a ton of learning in what you did. It will come with time. An incredibly successful entrepreneur I know said his break through happened on his 12th try. That’s a lot of projects.
Get away from the HN/SV bubble awhile. It’s like Facebook in that you only see the successes. The struggles are mostly manufactured fluff and don’t compare to what you put yourself through for 6 years. Most startups are built by people who took very little actual risk. Taking a year off your career at Google to go to YC isn’t a real risk, that’s like calling HBS a risk.
Don’t let people say “maybe starting a business isn’t your thing.” If a soldier got wounded on the battlefield, would you say “maybe war isn’t your thing” and that we should only celebrate those who didn’t take a hit? Of course not.
You’ve proven that you are an entrepreneur. You have the determination. You need to rest, recharge, and figure out what other skills need work and how you are going to counter attack. Whether it’s starting a business or doing whatever else you want to do in life. Seriously, building shit is hard and clearly you have the aptitude for it. Good luck in your journeys and know that you did something.