I was wrong about the bowel blockage. I overheard it on the phone. Turns out it was out of context or something. They're still only guessing about what's wrong with her. Fatty liver is the best theory, cancer comes in second.
We could only afford to let her stay another night, and that's with a mortgage payment spent into the red. After that we're bringing her home and I'm going to try to feed and water her as much as possible... try to reverse the fatty liver. I know the prognosis isn't nearly as good at home as it is at the vet. But they were saying it didn't look good at the vet, either. Hopefully she can last another two weeks so we can get her back to a vet then. If not... well... I'd rather have her die here at home, with us. Letting her know we love her.
The emergency vet has no way at all to work out payments, it's all up front. Except that they recommend Care Credit. So we applied, and they just gave us a tiny bit of credit, which we already spent today. I'll apply for the other options posted here and see how that goes. Still, it would be impossible to get any of that before we're supposed to pick her up at 8am.
Even if we took her to another vet... we're still seriously in debt with all of this, no matter how good any payment plan would be, they'd still want something soon. Seriously, I've been looking into giving blood and such, just to try to earn money for food.
I just have to cut myself some slack. We've done all we can for now. She has to come home in the morning, regardless. It's up to her, for the next week or so, to get better or not. Thanks for the all the suggestions and good vibes. Hope she feels them.