
What a difficult question, at the moment it would seem your dog is not enjoying at least 50% of her life, or at least that seems to be the case as described by you.
Positiveeating
drinking
enjoys grooming and personal attention
NegativePain
Deaf
No play
poor prognosis
Not looked at - walking, exercise & sleeping.
If she were mine and she is not getting pleasure from being walked and is not happy in the company of her fellow dogs particularly if she is unable to rest and sleep well I think I would be saying goodbye.
Sorry, that said only you will know how much of her life is, for her, pleasurable and only you will know what you consider acceptable quality of life for your dogs.
Would also say it is not just the dog who is suffering from her condition, your other dogs and your family to say nothing about you are suffering because of the way she is.
So sad for you and I hope I have not added to your pain but I think you wanted it straight and I think you know the answer.