It has been great to watch your progress and improvement documented on ranchers.net, Soapweed. It is actually inspiring to me in recuperating from recent back surgery, and with an ankle and at least one knee replacement coming soon, I need all the inspiration I can get.
I remember well what a 'mind' boost it was when my 'other half' got on a horse for the first time after his knee replacement almost three years ago, so am guessing the feeling was similar for you, though I realize your challenges are more than his were.
With some challenges these 'golden years' are giving us, we have discovered that the very best 'medicine' is the time we get to spend with our great grand baby. She is almost two years old, so may be similar experience you are having with your grand babies. Playing with them must be very good physical therapy, as well as good for the heart!!!
mrj