You sound sort of similar to me. I have a severely damaged spine that makes walking difficult & very painful, even standing for more than a very short time & have been warned about heavy lifting.
I too have a large garden to look after & over the last five years since the accident that caused my problem I’ve learned to adapt how I do things, I refuse to give up, I love my garden too much.
I don’t carry the tools you mention, I load them in a wheelbarrow & use it like a walking frame to take them to where needed. I don’t drag the heavy hoses to water. I’ve set them up permanently & just need to link up each part to the main hose that comes from the outside tap to the nearest part of the garden, then I use sprinklers if needed, also set in various parts.
Things like tree pruning that are now beyond me I get help, paid if needed.
Around the house I can manage mostly,( taking things slowly with short breaks, ) as you seem able to do, with painkillers. Outside, garden or round the village I use a stick as tripping is a real hazard I don’t want to repeat, last time I ventured down the garden without it I fell flat on my face on the stone slabs & broke my nose…..copious blood & looked like I’d gone ten rounds with Mike Tyson for weeks.