Krisy -
One housekeeping note... Can you start a new thread? We like to cap the number of posts on a thread at 50 so there's not a lot to read to get up to speed.
I'm relieved that your kitty isn't showing any signs of ketones. And it's even better that she's more herself today.
If Bella is on steroids for inflammation, you should probably sit down with whichever of the vets you feel like you can trust to discuss the bigger picture regarding treatment. Did the prednisolone help with her spinal issues? I would not want to suggest tapering her off of the pred if it has been helping. It is certainly possible that her diabetes is steroid induced. However, if a kitty needs to be on a steroid, you can work the insulin dose around the steroid. In other words, Bella may need a higher dose in order to compensate for the how she responds to the steroid.