Boiled white rice is just fine as a part of a temporarily bland diet for irritated intestines. It has good binding properties and little or no fiber to further irritate the gut (I actually use Minute rice for this purpose because it's so devoid of fiber...I have a box in the cupboard with "CATS ONLY" written on it). If this is a vet-prescribed diet, see if it's possible to add in some boiled skinless chicken breast. You can either mash it into the rice or chunk it up. Those two foods saved my butt when Assumpta stopped eating. The rice is fine, but if it's allowed, you might find that the boiled chicken mixed in makes her a more enthusiastic eater. No matter how bland and easy on the intestines, it's not going to do her any good if she won't eat it.
I've used a bit of cottage cheese successfully on other cats who didn't feel like eating because of diarrhea (some cats enjoy it, though not mine), and plain yogurt is good to help restore intestinal balance. Cream cheese can make a good "pill wrapper," as well.
But the cat has to eat. If she's not eating the bland diet as prescribed, call the vet and ask if you can add in the boiled chicken breast to tempt her to eat (tip: if you mash it into the rice, she won't just eat around the rice).
Oh, and if she's not eating well, don't put meds in her food or give them around mealtime, as it will just further a food aversion (Assumpta stopped eating because she associated the diarrhea and nausea with her food instead of with the antibiotic that was causing it). It's important that she eat, so don't do anything that will make her averse to her food and bowl. I ended up lying on the floor hand-feeding Assumpta little balls of boiled rice and chicken for almost a week before she started eating normally again.
Edited to add: Never mind, I see you've already added the chicken.