I think they're pack animals you know, and fitting in is more important than actually being truthful.
They have to fit in to the pack, or risk exclusion (and death) and so all have to have the same illness at the same time, no deviation. It's just inbuilt.
In order to assert hierarchy, pecking order, they have to have it worse, in order to be 'better' than you... and that's just the way the pack animal is.
I think if you are ill, they need to hear that from a professional that you really are ill before that can really hear that you are.
It's like they need to see a sick note or something, and be told what to do that lets them be top animal in the pack.
TBfair to my DH, if he's poorly, he goes and lies down and takes a lemsip, and doesn't come asking me for one (anymore, the initial training, and role definition still holds pretty much): and I believe him if he says he's knackered. I remind him I'm not a doctor /his mum / matron and he has to look after his health himself; he's a grown up now.
He doesn't whinge very much at all, he never really did, but then he went to public (boarding) school, and I think that a stiff upper lip is de rigeur. Training for the Empire ya know
I was brought up like that too: Military family. I don't whinge either, and I don't go through my symptoms with him - he's not a doctor... if I have to lie down, I just say: 'There's X in the freezer for dinner, stick it in the oven, I have to lie down'. And he does. A well stocked freezer is a wonderful thing
I think we both think of Parenting as a Military Campaign, in un-reconnoitered territory, and we are under fire!!! So we haul ass, and watch each other's backs.
I actually find whinging really offputting... I think badly of someone who goes on and on and does nothing about it themselves. I wonder what they're waiting for? permission to grow up?!