I'm so sorry to read what is going on with your little one. I know the pain and shock you are feeling and hope your baby can get well and is in the very best of hands. My Tibbe has a congenital liver condition that didn't become symptomatic until he was 4 or 5 years old. It's called MVD but we caught it fairly early on and began treating him with a very restricted hepatic diet.
Did your vet use terms like MVD(microvascular dysplasia) or PVH(portal vein hypoplasia) or something like that? You need to find out exactly what your dog has, become very familiar with the name of the disease and study and learn a great deal about it online so you can be your dog's best advocate as not all vets are that well-versed in adequate testing or treating the diseases of toy dogs. You will have to know enough to push for the best in consultation with an internist, testing and treatment yourself if your vet doesn't drive the process quickly enough or well enough.
Here is something to read on these conditions, written by a renowned expert in the field:
http://www.vet.utk.edu/clinical/sacs...2013-04-10.pdf
What symptoms did she have for the last couple of months before you took her to the vet?