Thanks everyone for you input. I was able to bring a fecal sample to our vet (she's an avian vet), and she looked at it under a compound scope as I stood there. It was free of bacteria, including cocci, and did not contain any parasites, eggs, etc. Therefore, she said it could be a some sort of toxin like a poisonous plant or mold on nuts (we have walnuts and almonds on ground) or possibly a different type of bacterial infection. I think she said hepatitis, all of which could be affecting her liver. She offered and I accepted an antibiotic (Ciproflaxacin) to cover most bacteria it could be and we started giving her it right away. However, at the same time we started giving it to her, she started eating and drinking a little more and she has improved ever since. We gave her yogurt, bread, and tomatoes to get her eating initially, with layer crumble always available, and then I started bringing her some green grass too. She recovered and seems to be fine now. Thanks again!