You're quite right about the pecking order! We rescued another cat once and Min insisted he leave, to the point of attacking the duvet where he had been sitting earlier in the day before we locked him back in his sequestered room.

We found him a new home in a house and with a family that I refer to as kitty paradise, Min watched us leave with him in a box, and come home with neither the cat nor the box. She was SO loving that afternoon and for the next week. We decided that she thought we'd bopped him on the head on her behalf.

Thanks for the good wishes. I'll call the night vet in a few hours and see if she is still breathing.