To get disability, you have to have a lawyer who specializes in disability claims. My mom has helped a few elderly disabled neighbors get onto it after years of them trying and failing - this is the secret to it.
SS stonewalls all people until a lawyer comes along and files the paperwork their way. Even our half paralyzed neighbor in a wheelchair couldn't get his until he followed the lawyer advice, and then it came together very quickly for him - just over a month.
The good thing is that disability lawyers don't charge you - they take their fee from the eventual successful claim. If you've filed previous claims for SS, once you win your case they have to pay you for all the months since your first filing.