I would also see that she gets a lot more water into her to dilute her urine.
Add water to wet food, syringe some into her mouth or however you have to do it. (And a D... wouldn't hurt either.)

I have a small semi-feral cat that has no control over her body functions. She smells bad most of the time! Sometimes I have to corner her to pull the poop off her rear. The vet does a 'sanitary clip' occasionally so there isn't any hair to capture the urine. I would be happy to do it myself and save the $$ if she would let me! I keep a blanket on the couch for the rare times she wants to sit there.