We can help you learn to manage Fluffy's diabetes. Can you give us more information about Fluffy's diet, insulin, dose and if you are hometesting.
Feline Diabetes can be easily managed through a proper diet, hometesting and insulin. For a diet, you want to feed a low carb/high protein canned or raw food diet. You do not want to feed dry food since it is high in carbs. That will make it much harder, if not impossible, to get Fluffy's glucose readings under control.
If you are not already doing so, you want to learn to hometest. This means testing a small drop of blood with a glucose meter before every shot. There are pet meters available, however, they are expensive to buy and use. Most people use a human glucose meter. A good inexpensive brand to use is the Walmart Relion Confirm or Micro meters. You will test the glucose, feed and then give insulin. By testing before every shot, you know if it is safe to give the insulin. Also, with consistent testing you will be able to determine if you need to adjust the dose. We can help you learn to do this. Hometesting will greatly reduce the chance of hypoglycemia and also eliminate unnecessary trips to the vet just to be tested. Glucose tests at the vet are not accurate any way. Stress can easily raise a cat's BG level by over 100. So if your vet is changing the dose based on that reading, your dose is probably too high for Fluffy.
What insulin are you using? Lantus, Levemir, PZI and Prozinc work best for cats. These are all long acting insulins and given twice a day. Insulins such as Vetsulin, Humulin and Caninsulin do not last as long and have steep drops in the BG levels. They do not work well in cats. The same with oral meds such as Glipizide, they do not work well either. You also want to start at a low dose, such as 1 unit, twice a day. If an increase is needed, it is increased by 1/2 unit and wait at least one week before it is increased again. Hometesting will let you know if the dose needs to be adjusted.
We can help you learn how to manage Fluffy's diabetes and give suggestions that will make it easier for you.