Hi and welcome Chelon and Sadie. You have found a wonderful resource for information and support while you learn about feline diabetes and what effective treatment is, plus a world wide support community.
Yes, it's overwhelming just to get the diagnosis. And I, for one, applaud your decision to treat her disease and not let her get sick and have to put her to sleep. We don't put human diabetics to sleep, we learn about proper diet, insulin therapy and how to test to see what the blood sugar is. That's what we do for our "sugar cats" too.
You will learn the difference between a syringe and pen, I'm not sure what you refer to with gb or gc..but BG is blood glucose (blood sugar). You will not want to start treatment and then stop giving insulin if you are out of town. We will try to help with finding options so she gets what she needs when you are away.
Depending on the size of the cat, what the diet is, and what insulin is prescribed we can make recommendations on a starting dose, or offer input on the vet's starting dose. Doses can be decreased if diet changes and the blood sugar goes down, or increased at need, by small increments so you don't go past the best dose. We can help you learn to test the blood sugar, find affordable supplies and offer lots of tips and support while you learn.
Chelon, we all started in the same place..at the beginning. I remember very well wondering if two old duffers were going to be able to take care of a diabetic cat..well, we did. We fumbled, and bumbled a bit, but with the information and the support found here, thankfully Idjit is in remission. That's a diet controlled diabetic, no insulin. That's the ultimate goal, but not promised, it doesn't happen to every cat or even right away for every cat.
So, essentially, it's going to be up to you to decide what you are willing and able to do to help Sadie.
No one here is going to be able to give you pat answers all the time, every cat is different and they wouldn't read a manual if there was one. We can offer education, suggestions, input, advice and lots of support, but you have to do the work.
Are you interested in learning to test now?, you can learn and do it even before starting insulin. We need to know what her diet is and if the vet recommended a diet change. Let's start with that in a new thread in the Main Health forum
HERE so that more members can meet you and Sadie. This forum is only the welcome mat, so come on in and let's put collective heads together to figure out next steps.