SOMEhow she got it in her head that she needed a new register book for the checkbook, when she already had one. I think. At least, this seemed to be the centre of the logic trap.
So she's sitting there with the old register which she stopped using a week ago, the new register already in the checkbook, and another blank one (And I am cutting out even more confusion and just rolling with this.)
I spent nearly thirty minutes trying to get us out of this;
"Okay, this book is done, I need to make sure I carry the information over to the new book..."
"The new book is already in the checkbook. And has been for a week. And you need to go back a page for the first entry."
"Then what's this book for?" "That's a blank new one."
"Okay...it says here I have a voided check? Oh! Here it is."
Takes it out of the checkbook, sets it aside. "Oh wait, I need to put this in the checkbook so I don't lose track of it."
Picks it back up and puts it RIGHT BACK WHERE IT WAS.
Looks around for a bit.
"Okay, this register book is done, I need to make sure I carry the balance over to the new one..."
"...The new one is already in the checkbook. And has been for a week."
"Oh, it says here I have a voided check? Where is it? Oh! Right here!" Takes it out. Remembers to put it back.
FOR THIRTY MINUTES.
Even *after* I grabbed the blank book she kept trying to use despite already having one she's been using for a week, this kept cycling around in smaller circles. And then she had another one somehow!!
Until I *finally* got her to put the final check number and end date for the old register on the front for bookkeeping purposes, yanked it from her hands, held it up in the air and shouted, "DAD TAKE THIS FULL BOOK AND PUT IT WHERE YOU STORE THE REGISTERS SO WE CAN ESCAPE THIS HORRIBLE CAUSAL LOOP!"
And again, I actually left OUT a lot, because A) I'm recovering from a fever and am likely forgetting stuff and B) it was the half-listened to stuff I heard her going around in circles on that brought me over there in the first place.
I am just grateful it was ME who interceded and not my dad, because while this was frustrating, I actually think it's a funny story, while recognising the deeper potential implications here. And while I was more than willing to cut my way through the Gordian knot with a butter knife, my dad would have tried yelling and hammers.