It's nice to hear that you've found some peace! There's no point in being the best if you will crash and burn quickly.
Child rearing does not last forever though, and if you practiced nothing for those 20-30 years you will fall into the same traps again. Accepting mediocrity is not freeing when it leads to giving up all efforts (And that’s a recurrent scheme)
One thing that has helped me a lot to find peace here has been becoming a father. Culturally, it comes with a kind of license to finally just accept mediocrity which I find freeing. Bills are paid, I can watch my son grow up, doesn't matter than I'm not the best at anything.