Hi!
I am going through the same problem with my cat! you can see my thread in this forum but its called "help kitty eating food not for him" ....(if you read the thread and posts you'll understand)
i guess the best advice i can give you is to FIND A GOOD VET! if you already have i congratulate you, bcz my first vet was pure hell, he didn't even care, i think the vet is one part bcz its the one who is going to guide you in the right direction, and the other part is of course yourself, keeping up with the medicine the feeding, i mean there is only so much you can do, you'll have to leave the rest to your cat and pray that he or she gets better
i know i have done everything in my hands to help my cat and it is paying off bcz she is getting better...but the last few weeks have been really scary, it is sooo scary to have a sick pet, bcz they are your family! so please hang in there!
so cheer up keep trying
! i hope you and your kitty the best and hopefully she'll recover completely!!
p.s. feel free to send me a msg if you wanna share stories or compare medication...or just for support!