I am now 79 and a widow living alone. Whilst intellectually accepting that I am older (not old!) I still find that in some circumstances my body or my mind tends to forget. Allowing enough time to walk somewhere as I am now, is both frustrating and irritating, as have always been a fast walker up previously . . I plan some journey and of course in the car that still matches but I know how long it used to take me to visit somewhere , or walk along a promenade or whatever, and have to remind myself to add on a fair bit longer these days. On bad days I know however much better that cafe upstairs is, I would struggle to get up the stairs, so it has to wait for a better day.
I think the hardest thing is to now have to be vague or put a sort of condition on arrangements. So I would suggest a visit to the coast or up the dales to a friend and we would make a picnic and off we would go. These days I always have to put in the proviso that my back will allow me to do whatever it is, so have to be able to ring up and have a rain check on the date if I am having a tough day, but I hate having to admit defeat, and would rather go equipped with my binoculars, so that whilst I cant walk with the others I can look at birds, shipping or get a closer view of blossom up the dale.
Still as the saying goes better than the alternative!