The reason why you feel annoyed when you’re actually just tired

There's a specific kind of exhaustion that makes you into a person you don't quite recognise. The person who snaps at their partner for asking an entirely reasonable question. The person who cannot make a decision about something small and feels genuine distress about it. The person who is made furious by nothing specific — and then made worse by noticing they're furious about nothing specific. She is not difficult. She is running a nervous system under neurological constraint.