Blind dogs do very well once they adjust. Most diabetic dogs like my Lady go blind (she was one of the very few that didn't) and their owners always describe how frightening it was in the beginning, but how well they learn to cope later on. I still remember one woman's joy at being able to jog with her Lab again. Once her dog regained his confidence, she tied his leash to her waist so they could run together again.
This website has been very helpful to owners of newly blind dogs:
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