I have a life philosophy about this: failure is the path to success (I've never learned anything by being right).
It can be hard to maintain the mindset, but it's actually true -- we learn from our mistakes, so nothing is a failure as long as a lesson was derived from it.
If you can maintain that mindset, it takes a lot of the stress out of things!
I don't do woodworking, but I do fairly complicated electronics projects as a hobby, and a similar effect happens. I made a special display case where I put those failed projects on display, next to the final successful one. It reminds me that the failed example was just a stage in development and makes me feel better.
The final product was epic, and I use it every day, but the failed desk was too big to keep.
I have had a number of failures at all phases of projects. One was 20 hours of work and a grand in materials that I were totally junk (I had to pay more to drop it off at the dump). One was fairly low material cost, but ~40 hours in it was ruined.
Now I make duplicates in case of failures. My last project I got material for 10, was able to actually get 7 blanks due to cracks and knots, 5 didn't get tear out so bad they were worthless, and 4 at the end after a final gluing mistake. One for me, and two that were gifts for friends. One spare, out of materials for 10.
I get anxiety about starting new projects because I worry about how much material to get to account for my mistakes.