I hear ya Doc. My back is only good for about 10 or 15 minutes in the grocery store pushing a cart. Flying control line is pretty much out of the equation. Still fly my Old Time free flights with ignition engines and radios, once in a while at my Grand daughters farm. Even though that is illegal soon without a transponder.
I still have most of my planes, and enjoy my time remembering how they all flew. I have given away a few to my great Grand kids to hang in their rooms.
And, I still enjoy running my ignition engines on the test stand in my back yard as most of the neighbors are gone all day during the week. And I live at the end of a dead end street in the middle of a small community of 10 houses in the country.
I do really miss flying and the comradery though. Made a lot of friends over the years. No one really understands what we do except other control line flyers. I started flying models in the late 40's, and it has almost been continuous all my life in one form or another.
So, I still enjoy my planes even though they are all static now. But they all bring back some great memories. I have some I built 50 years ago, still flyable.