I was born in Boston, lived in Cambridge, Beverly Farms, Swampscott (then moved to Germany / Florida / California), and Wayland.
I struggle with the horse-keeping situation out here, but Mickey’s different than your horse in that I don’t think he’s ever known any different. He has it better now than where he came from (So. Cal) where he didn’t have green grass to eat, turnout to hang out & move around during the day (but he did have an in/out stall that was probably 14 x 28 or so?), or someone who paid as much attention to him as I do. So I think he’s happy. According to my animal communicator, he says he has no complaints (unlike the other horses who complain a lot)! 
I try to provide as much variety in his day as I can and that’s how I cope with it. He does get turned out in the morning, and during the good weather, I turn him out after I ride so he can cool down - or I take him for a mini trail ride or graze for awhile so that he can just be outside. When I don’t ride, I put him in a paddock to just hang out and visit with the other horses (they can’t touch each other, but I know he flirts with all the mares!). I like to keep him outside of his stall as much as I can, which isn’t nearly enough…
If you can’t get to the barn anyways and don’t mind him being far away from you, you might check out barns on the coast…the Newells have a place in Pescadero with (I would imagine) lots of land and I’m sure their horses are out a lot.
“Oh Mickey you’re so fine, you’re so fine you blow my mind, hey Mickey! Hey Mickey!”