I just got back from holding Spirit while she was euthanized. The ultrasound found a very large mass in her stomach along with enlarged lymph nodes there. That's almost certainly lymphoma and there's no real way to fix that. I could have tried chemo, but it wasn't likely to work and I don't think she'd like that. So I could bring her home for about a week with palliative meds or let her go there.
I told the vet I'd call back when I decided and I remembered how the last few weeks, she hasn't been getting into my lap anymore and if I lift her up, she goes back to bed. I decided letting her go now was the best. I'm going to have to figure out how to store her bed (the other cats are too big for it) and what to do with the large triangular litter box. The small carrier can just go in the storage room.
The vet called when I'd had four hours of sleep so I'm going to bed now.