Oh Tuppence I can relate to this! Maybe not quite as extreme (no joint hairdresser visits!), but my DH frequently wants me to accompany him on any trip out. E.g. he's in the middle of a project outside and finds he needs more screws. "Going to B&Q - do you want to come?" Yes, sounds innocuous enough, but if I say no (which I often do, especially if I'm in the middle of doing something myself!) then these little refusals are stored up and used against me, "oh you never want to do anything with me, do you!" (always shouted, always accusatory).
Equally when he sees me putting my shoes on, he immediately asks "where are you going?" with an offer to come with me. I've so often had to say no to him, that I just like to go out by myself and have a browse around the shops, but I know I'm risking a row each time I do this.
What I've taken to doing is getting ready, quietly, upstairs, then coming down, picking up my keys and bag and saying "I'm just off down the road, won't be long" not giving him a chance to draw breath, never mind invite himself along. Then if I want to stay out for longer than I implied, I'll text and let him know that I won't be back till xyz o'clock after all.
The thing is, when we were both working, I worked Mon-Fri and had the weekends off. He worked on Saturdays, so I was used to pleasing myself then, often going out if the weather was good, visiting different places in the area and wandering around. But as soon as we retired that all changed and I felt utterly stifled. I've had to dig my heels in, and to be fair, after several years, the moods and rows are less frequent. So maybe you need to take a very firm stand and tell him in no uncertain terms that since you are not surgically connected to him there is no earthly reason why he should accompany you everywhere, 24/7!