Yeah, as I say, for those not already suffering.

Those that were suffering, would be abandoned. Once people realise it’s hopeless, their care would cease. Maybe not initially, but inevitably. Like the guy from The Beach that gets wounded by the shark. The rest will go on and the sick will be forgotten.

For the planning aspect, lack of notes shouldn’t matter. Populations would coordinate locally, and as long as you can remember what you’re supposed to be doing the “next” day, you’re golden.

So basically marriage? ;)

Yeah, relationships would begin and end as normal I’d expect. The only limitation to meeting new people is how far you can reasonably travel within the window.

Potentially, but I can’t imagine your first thought would be “I must be reliving the same day” rather than “I could have sworn I took the trash out yesterday”.

I’d definitely be questioning my sanity before the third law of thermodynamics.

What I find interesting is that potentially the time loop wouldn’t even be discovered immediately. Most people would wake up in the morning and head to work as normal. There wouldn’t really be an obvious sign we’re in a Groundhog Day, since the usual indicator of that in fiction is that other people are doing the same thing they did yesterday. Which they won’t be, if everyone is experiencing it.

There would be sparse stories worldwide initially of people claiming that it’s the same day as yesterday. Your phone might still have yesterday’s date, which most will attribute to a global software glitch. Maybe some investigation is done, hardware that tracks the skies shows the earth in the same position. But final, global, acceptance would filter down slowly, since you’d only be getting news for one day via technological means, and the only up to date information you’d reliably get is direct communication. Unless of course the technology still works - phone calls etc, wouldn’t just immediately be unavailable.

If you lived remotely, off grid, or alone, how would you even know unless you started to notice actual physical repetition. Rain starting at the same time every day etc. It’s genuinely fascinating.

If everyone resets, and their memory is retained, then perhaps less would change than you’d expect. For example, if you wanted to organise an event for the following day (ie today, but again), then it’s still possible to plan. In which case, many things about life actually stay the same. Only the physicality of things actually change. For people not already suffering, it’s actually a great mechanism for freedom, since the shackles of money, food, health etc are no longer a concern.

Because cows calve calves