Morning leeosteo~
I can only speak for myself and how I feel about the choices I've made..as I would hope you all do as well. What works for one..may not be a good fit for others..we all know that.
Yes..life in general doesn't get easier for any of us that live longer..life itself is a diminishing skill to maintain!
I will be 79 in a few months and honestly..most of the time I feel great and ageless...and yes..I admit to stairs being uncomfortable..because of knee pain from OA...and yes..if I lift anything heavier then 8 lbs..I get mid-back pains..later....so I try and avoid lifting heavy things. But...I just painted my kitchen..up and down my step ladder..reaching high up....not an easy task...I did feel like I had over done myself that evening..so I sat with my hot packs on my back and hips and took 1/4 of a percocet and used my infrared belt as well. I went to bed...next day..no more pains! I feel so very fortunate to not be in persistent pain. I got myself a little pedometer that I wear to be that little reminder to get up and walk..go for a walk..doing something, I tell myself!...just keep moving....and, must say..I feel better for it!
We may not be able to rebuild bone density as we age as easily then when we were young and had dense bone structures..but we also don't have to give up on staying as fit as we can..without stressing over it all...and the inevitability of aging. I'm learning as I go...always looking for more comfort in my life...and peace of mind. I am so very fortunate to have only myself and my kitty to take care of now...that's quite enough for me to deal with...more time for play!
Oh...I do take a lot of supplements and eat a healthy diet..I'm still 5'4" and weigh 126lbs. Feeling great today!
I wish you all the best you can be!

Where did you learn that it is impossible to regain bone density post menopause?