i already said this in my post.
i'm reacting to literally as the post had been written.
which included saying they 'think s/he was having fits'.

re fits: just as people, most dogs can live a quality life with this condition under drug and lifestyle management....
i have direct experience of this.

being blind and deaf ***by and of themselves*** arent often quality of life euthanasia issues.

When she was too terrified to leave her bed, and would panic if her lead was put on, because she didn't know what was happening (it literally came on quite suddenly, and the vets did not know why) then it obviously affected her quality of life. If she had still been happy, we would have obviously found a different situation, but she wasn't. It broke all our hearts, but everyone involved knew it was the right thing to do.
This dog loved life right up until the week before she died, then was all of a sudden too scared to do anything. She's had a long, happy life, and we wanted her to die with a bit of dignity.

im sorry to hear what happened.
as i said in my earlier post, if your vet said your dog needed to be PTS for medical quality of life issues, then i can certainly understand that.
i was reacting to the wording in your original post.
no disrespect intended, but if you go back and re-read this, the way you have written it can be seen as your dog got old and grumpy, so you put her to sleep just for that reason.