I think this is pretty key and doesn't get enough attention.
In child psych they talk about "resilience", the ability to get back on your feet when something knocks you down. It's hugely helpful for kids.
But it's also critical for adults, and especially successful adults who frankly don't have a lot of experience being knocked down and getting back up again. I suspect that most anxious successful adults underestimate their own ability to bounce back from failure -- many of us think that we got super lucky and at any time something could destroy it all, not thinking about how would take advantage of other opportunities already available in the face of failure in one domain.
I suspect another piece of this is the lack of spare resources (money, time) to handle external shocks. We're so busy that when one thing goes wrong and needs extra attention/money/time, we know it comes at the expense of something else -- and we feel that expense strongly.
Curious for others' thoughts on these.