The other thing you could do besides a cone collar is use an undershirt, if she is a small cat you could get a loose sock and cut holes in it for her arms and just let the bottom part be snug against her belly. Check with the doctor on this, but my veterinary center sent my cat Lulu home with this when she had a different surgery and it worked fine. Also they make soft collars now, which is a good deterrent and does not really bother the kitty. Plus, there are a lot of cats who don't even mess with their stitches at all and many vets send kitties home with nothing. Last but not least the vet can put apple bitters or another bitter antiseptic on the incision to keep the kitty from going after it.
On the medicine, I know there are cats with FIV and feline leukemia who are on steady antibiotics but since your cat has tested negative It is distressing to hear that she is still in this situation. I would definitely ask the vet to please explain the rationale for continuing this treatment this way. Your cat needs time for her healthy bacteria to develop so that she can have sufficient immunity to fight off whatever (micro parasites?) is attacking her system. I would ask the vet why not try probiotics instead of antibiotics? I do apologize in advance if I missed something in this area already. But normally in a young cat it is a microparasite that causes these kinds of problems. I would be dosing my kitty with probiotics and using pumpkin to help with her stools, wiping fingerfuls off on her tongue.
On the medicine, I know there are cats with FIV and feline leukemia who are on steady antibiotics but since your cat has tested negative It is distressing to hear that she is still in this situation. I would definitely ask the vet to please explain the rationale for continuing this treatment this way. Your cat needs time for her healthy bacteria to develop so that she can have sufficient immunity to fight off whatever (micro parasites?) is attacking her system. I would ask the vet why not try probiotics instead of antibiotics? I do apologize in advance if I missed something in this area already. But normally in a young cat it is a microparasite that causes these kinds of problems. I would be dosing my kitty with probiotics and using pumpkin to help with her stools, wiping fingerfuls off on her tongue.