It's interesting about the decision-making. I've always known people like this, who couldn't bear to make a decision because of the losing out on one option, but I think there were fewer of them.
About the robustness - yes, it's a weird thing. My DC school have a big thing about "resilience" and have assemblies telling them all to be resilient, but it isn't going to work if you are generally brought up to believe it's a disaster if you ever experience a negative feeling.
I'd almost call it stoicism except that makes me sound about 250 years old. It's subtle, because stiff upper lip and repressing/bottling up emotions is NOT good for us and it is good that people are better at talking about feelings, etc.
It's more that they often don't have the ability to see that finding something difficult, being upset or having a shit day is part of life. You shouldn't pretend everything's fine and bottle it up, but you could just realise that something like feeling awkward in the hairdressers, or someone offending you by having a different opinion, is not a big deal in the scheme of things. You could even laugh it off.