I had a similar feeling some 10 years ago after my first startup failed. I felt that I had wasted one year of my life and was very bitter about the failure and the personal sacrifices that came with it.

In time my thinking came around. I better understood my limits, knew my preferences, and developed some new capabilities. I was also better able to navigate startup #2 which is still going great as a bootstrapped company. My cofounder ended up on a corporate software dev team, and is also doing well.

Bottom line: things will get better. Regard this as a learning experience that helped determine a more rewarding future path (probably not doing your own startup, but that's OK, too)