ditto everything rabid said. my cat stopped eating just over a year ago and did develop fatty liver. when we finally realized something was up and brought him to the vet we were told another few days and he would have died. he had to have blood work done which is expensive, we managed to get by without an ultrasound luckily cause that's about $500+
we had to feed him vet-prescribed food from a syringe every couple hours for about a week. it involved one of us holding him and the other forcing the syringe into his mouth and basically forcing food down his throat. it was messy and heartbreaking and we got like no sleep.
after a few days he started to get his appetite back and i started buying one of every brand of food i could find until i found one he liked.
i narrowed down that he doesn't like seafood (go figure a cat that doesn't like fish) and that was the problem. i had bought seafood based canned food by the case to save some money and he didn't like it.
now i know that it wasn't the brand he disliked but i still buy some of every flavour but the seafood ones and alternate them so he doesn't bored of any one flavour. every now and then i buy one can from a different brand just to give him some variety.
think about it, would you want to eat the same thing day in and day out?
the fact that she's still eating her dry food is possibly a good sign. maybe she's just bored of her canned food, try a different brand, try several brands and flavours.
it is true that changing foods too quickly can upset their stomachs but i find it's less of an issue with canned. try to stick to similar quality and ingredients.
you don't have to spend a fortune to get a better quality food. a good place to start is don't buy anything that lists "by-product" in the ingredients. it's garbage. and anything with grains for filler, and definately anything with ash you want to skip. check your health food store, there are some natural brands that are small companies or local companies that aren't big enough to distribute to pet store chains so they sell to specialty stores and health food stores instead. they tend to be cheaper than the high end brands from chains.
also if you have a petcetera near you they have their own brand that is incredibly cheap and while i can't attest to the quality of the meat, the ingredients are literally like "fish, water" and that's it. no junk in them at all. the one i went to only had fish based ones so i don't buy them but i did get a couple to test him with and they had real whole shrimps and calamari rings and real chunks of fish. i was amazed considering how cheap it was.
whiskas and any other brand you typically find in grocery stores or department stores is like the equivalent of you eating mcdonalds every day
one more thing, when you go to a higher quality brand you may find your cat actually eats less of it. cats will instinctively eat only what they need (for the most part, there are some piggies out there lol) so if they are getting a low quality food lacking in nutrients they tend to eat more of it to make up for it. a higher quality with more concentration of good nutrients means they generally need less of it to get their daily requirements therefore they will instinctively eat less. you might notice her pigging out a bit at first because it's new and seems like she's getting a treat, but once she's figured out it's there to stay she'll balance out. so in the long run going to a more expensive brand doesn't always cost much more
I'm singin' here to get rid of fear
Hope it disappears right here with the rain
But I know life is pain, not like a fairytale
Meaningless to pray, so just goin' on my way