How To Make Decisions Under Stress
Recently I had to make a big life decision ("one way door", as the kids say) under a huge amount of stress. I would wake up at night with my stomach aching and be unable to fall back to sleep because the thought of this situation just latched onto my mind, like some kind of Lovecraftian octopus reaching its tentacles into my brain.
I was very aware that my brain wasn't functioning well, but that also that I wasn't going to get a new brain (literally or metaphorically) before the deadline for this decision was up.
As best I can tell, there are only three options for what to do in this situation:
1) Decide based on gut instinct: your brain is shutting down, but your gut is still functional.
One downside of gut-decisioning is that your gut is in (literal or metaphorical) fight or flight mode, and I suspect that whether your gut says "stay and fight" or "fly away" is more of a default property of your character than a specific response to the details of your situation.
Another downside is that it's hard to tell if your gut is wisely responding to the long-term implications of your current stress reaction, or just... trying to avoid your current stress situation. I think it's possible that your gut would scream Get Out just to avoid acute but short-term pain, even at the cost of the long-term best solution.
2) Defer to a friend: your brain is shutting down, but your friends still have them.
If there's someone in your life you trust enough to have context and share your values and have your best interest at hard, and who has presumably already heard you complain about the situation at length, you can just... ask them what to do and then defer to it.
I think this only works if you're actually so certain in this person that you can defer to them without re-analyzing and evaluating their conclusions, at which point you're not really deferring but just using their opinion as one extra input for your brain and/or gut.
I sometimes suspect that, since other people's decisions are so easy and obvious where your own decisions are impossible, I'd be better off swapping life-decisions with my most trusted friends and let someone else "pilot" my life without my fears or sloths or insecurities getting a say. Of course I have had this conversation with friends over the years, and of course I've never actually followed through with it.
3) Follow a principle: your brain is shutting down, but your eternal principles are eternal.
In the moment of great stress, I felt like I re-appreciated the value of having and hewing to eternal principles. Of course there's still some subjectivity in how you apply the principle to your situation, but I couldn't help feeling like a person with a clearer and sharper set of Predefined Principles than I have would have been able to respond to the stress by saying: "well, I always X" or "well, I never Y" and then make the decision that way. (As always, you wish you'd stored grain while the going was good, but when the going is good who's thinking about grain-storage?)
A funny thing is, you also have these same options when making normal decisions under non-stressful conditions. In that case you do also have a fourth option of listening to your rational brain, but your rational brain is probably still limited (though not as limited) and you might still be better off using one of the other three.