Ohhh, that's so hard to see your pets in pain! I'm sorry if you already mentioned, but do you use wet or dry food<kibble> with your kitty?
I ask because cats are not meant to eat dry food. There is not enough water in dry food for optimal long-term health of a pet carnivore, which is what a dog or cat is. Kibble is ten% or less moisture -a natural diet for a cat or dog is prey-based, which means mostly water. Many people feed cats dry food because it's convenient but it really bad for cats in particular, because of the lack of moisture. Lack of moisture over time can lead to chronic UTI's and other urinary-related issues. Holistic vets will tell you never to feed dry food to a cat.
So, if you are using dry food, what you could try to do is put a small amount of warm water in the food, just to moisten it, and then hide it where she has to come across it, so it simulates her hunting it. You could also portion it out and put some of the usual in her dish<that way the dish is not all "weird" and contaminated>and set some aside on a shelf or in her path for her to find. Over time <for cats that might be weeks or months up to a year> gradually increase the amount of water in the food, and maybe you could transition slowly to canned food, which is much more recommended for cats. And no, kibble does - not - clean teeth - that's a myth.
If you're already using wet food, try adding water to it anyway. I feed only raw but still add warm water to my girl's food. I also use cranberry powder in their food to help prevent bladder infections. I always read the label of the cranberry powder though to make sure there is no added sugar or xylitol <potentially toxic> in the powder - if I use a human supplement.
Another product I use for prevention of UTI's is called Tinkle Tonic - a non-alcohol liquid herbal supplement formulated spec9ifically for dogs and cats by long-time master animal herbalist and author Greg Tilford. A link about the product is here:
http://www.onlynaturalpet.com/products/Animals-Apawthecary-Tinkle-Tonic-Herbal/148001.aspx
It has a number of anti-inflammatory and soothing herbs; I've been using it especially since my youngest is still going for water therapy so she's a lot wetter consistently in that area and it makes it more ripe for irritation or infection.
Sorry about your kitty, it's hard