Great post @lymepoet, upvoted.
My "revelatory moment" was in 2007. I'd been asked to play one hour each week in the Nursing Home ward and the Alzheimer ward of the VA hospital where I was at the time.
One hour each.
I was only playing what I had in my head, songs I'd known for years.
The very first day in the alzheimer ward, I was playing "The Tennessee Waltz" and a little old lady in a wheelchair piped up and said "My Husband and I used to dance to that song", well I was very pleased, but the reaction of the staff was ASTOUNDING!!
"She hasn't said a word in several months!!!" they said.
Working in a memory care facility is extremely stressful for the staff, and I saw that during my performances, the staff could relax, even interact with their residents in ways they normally had no chance too, because they were always chasing patients, trying to keep them from hurting themselves or getting in fights with other patients.
Now my playing music for the old folks (I am no spring chicken) is just about the only bright spot in my otherwise rather dismal existence.
I hope I haven't taken too much of your time.