[Salvey]

Jill reminds me of Frank Sinatra’s last wife. Kept him up on the stage performing when when his shelf life had come and gone.

Indeed. A good friend was in the orchestra that backed Sinatra in Vegas. He confirms what you stated about Barbara Marx. He said that in the early stages, Frank needed large cue cards from which he read the lyrics. At the end, he couldn't even read the cue cards.

[frank ballenger]

Decline of Frank Sinatra.
Sad story. He had arena and concert halls with screens in all directions for the lyrics but at times still said to the audience “I don’t know where in the hell I am in this song” for ones he had sung all his life.

At least one biographer said the audiences loved him and would have been content with him sitting on a stool, holding a microphone under a spotlight on stage talking about his life and stories about friends. But he pushed himself to sing again.