We had an Australian Kattle Dog and found out she had lost her sight. Took her to the vet and he said she had been diabetic. Being an outside dog we never caught it until she became blind. I, too, asked about surgery and took her to a specialist. The surgery was about $6,000, was not guaranteed and they said it would not restore her eyesight completely, she would only be able to see shadows. Back to the original vet and he said in her advanced state she only had six months to live. Two insulin shots a day and feeding twice a day let her live another FOUR YEARS!....she still played ball and romped in the backyard as normal. The only thing she didn't want is to come inside the house and we had to leave everything in the backyard as it was or she'd bump into it.
With our current pet, we found out this past summer that she too was diabetic. Some dogs are more prone to the disease than others. We are currently giving her the same treatment with the meals and shots and her eyesight is fine so far. We hope to let her live her life to the fullest.
Hope you make the right decision. I thought the surgery was too expensive. They will learn and adapt.
P.S. The way we found out she was diabetic was she started drinking more water than usual and peed in the coach which she has never done. Took her to the vet thinking bladder infection but tests showed the diabetes. If your dog is drinking more water than usual, take her to the vet asap. Early treatment can help your animal enormously.....Dennis