Post-exertional recovery with M.E. It goes a little like this:
Healthy person: ‘Hey friend, fancy meeting up today for a coffee and a catch up?’
Person with M.E: ‘Hey you, umm I would really love to … ‘
Healthy person: ‘I hear a ‘but’ coming … ‘
Person with M.E: ‘Yeah, but the thing is – I washed my hair yesterday.’
Healthy person: ‘Yeeeeah, and … ?’
Person with M.E: ‘That’s it. I have nothing else to add.’
Healthy person: ‘Wait – that’s the reason why you can’t hang out with me today?!’
Person with M.E: ‘yup – nailed it! But I should be able to squeeze you into my diary next week. Looking forward to it already! Byeeee!’
(Then hangs up. The person with M.E embarks on an entire day or week’s rest to recover their health from washing their hair, whilst feeling really excited for their coffee date the following week.
… Meanwhile, healthy person is left wondering what the fuck just happened, whilst discreetly sniffing their armpits 
).
(Full disclosure – this is an example of how life used to be when my M.E was more disabling. Nowadays, I’m much improved – thankfully).
