In terms of actual writing, I asked a good friend 'what does your character believe that isn't true?'

My antagonist believes in a perfect state of peace that they never actually experienced. They long for a state of being that didn't really exist, and it robs them of all joy in the present.

Oh no! You were so prepared right out of the gate! Oh well, that’s why we have a whole month, and why we practice being kind to ourselves. It’s also why I write escapist garbage 😁

The whole “it can’t be that bad” thing. No matter how much we promise that it is in fact that bad, they can’t assimilate that idea. It’s too far from their experience.

It’s not the same as ‘all my bits hate each other and actively want to go their separate ways. So much so i don’t bother with the ER anymore, I can put this stuff back in at home.’

I think people have a great deal of trouble accepting disabled reality.

I see it in chronic pain circles sometimes too. A conversation about chronic joint pain from
Hypermobility will sometimes get a dismissive comment from someone who has indeed dislocated something. Once. For which they got time off and acknowledgement that this turn of events sucks.