I'm sorry you got bad news. I know lots of dogs and cats with diabetes and they have a fine quality of life. Others do not do as well as they have, as you are worried about, kidney damage already.
Do what you need to do and don't feel bad either way. If I were you I'd have a frank discussion with the veterinarian about the chances of having a good quality of life. And that you would like to do as much home care as possible if you decide to treat. I suspect they are wanting to check her blood level very regularly (ketones) is why they want to hospitalize her, maybe you could bring her back at regular intervals. But giving fluids is not difficult, especially if your dog is a good patient. In addition they usually want to do a curve, where they see how she reacts to food and insulin, before they can give you her correct dose. First they need to stabilize her and then find her correct amount of insulin because it is different with each animal.
We often see a diagnosis of diabetes turns into a euthanasia visit at our clinic. You would certainly not be the first family to opt not to treat. Not everyone has the luxury of being able to have the choice. If I were faced with this right now, I'd have to put my beloved pet down.
You have probably already given this dog an awesome life full of love. Cherish the memories.
Ok, this isn't about a dog, but a horse, my 1st horse, Binty.
I met my friend RU a few years ago. I used to lease a horse off of her, but she knew I wanted my own. One day she called me and wanted to know if I wanted a chestnut, Arabian mare. (I had just prayed for a chestnut Arabian mare a few days b4, but had told no one.) I asked her how much? She said free. The owner had died, and the family didn't want her, they just wanted to find her a good home. Needless to say, I took her. It was, for me, a dream come true.
January 26, 2006 I got a call from her. Binty was cast, and she couldn't get her up. I broke all the speed laws getting out to the farm. By the time I got there, she and her husband had managed to get her on her feet. I was relieved, but my relief was short lived. It didn't take long to realize that the reason she was cast was because she was colicking. And, I couldn't get the vet out. All day long, I kept calling. Finally, the person in the office asked if she was still trying to roll. I said no. She said, well then, she'll probably be fine, but if you want to, you can call another vet. She gave me the number, and I lost no time in calling him. He came right out, and sent me home for my trailer. I took her to New Bolton. I was hoping I'd find a pile of poop in the trailer when we got there, no such luck. I was hoping it would be just a simple colic surgery. No such luck. The reason she colicked was because she had a tumor in her small intestines. As a result, she had several feet of dead intestines. There was the chance, but no more than that, that they could save her. They would have had to cut out the dead intestines, and do a bowel resectioning. The cost would have been around $10,000.
I won't lie. I was so tempted. But, then I asked myself, is it fair to her? Plus, can I really afford this. And as hard as it was (and still is), I made the decision to put her down. She was 22. I had her for just over 2 years.
Last January, I had to make the same decision w/my dog. She had cancer, and I could have spent the money on chemo for her, but it would not have added much to her life. Plus, it would have been hard on her. She was not quite 12, and I had had her since she was 5 weeks old. (The mother got quite sick, so they had to get rid of the pups early.)
Neither of these decisions were easy. And, I still miss them both. But, out of my love for them, I let them go. Love isn't selfish, but seeks the best for the person (or animal) loved.
I know you love your dog, so you need to do the same thing I did, and ask yourself, what's best for my dog? If it's the treatment, then go for it. If it's putting the dog down, then do it. (I hope this doesn't come across as preachy, it isn't meant to be.)
What a difficult place to be.
Ultimately only you know what is right for you and your pet.... and know you will get support from me any direction you choose.
Thank you all for your prayers. We decided to put her down. She was very sick and the treatment was too costly with no guarantee of a good outcome. We miss her terribly. It is so hard to believe she is gone. I would like to know how to prevent this from happening in the future as we have another toy poodle.