At night we put the cat into the “sun room”, a room on the back of the house with a tile floor and a bunch of windows. That is the room the litter box, food, and water are in. In the winter we put a heater next to the cat’s bed that’s on a timer to run from 10pm until 6am.
If the cat didn’t want to go in there, I’d let it chase a laser pointer dot into the room, then it’s good night kitty.
Good to hear Dung Beetle!
We have two doors to our bedroom - a sliding pocket door and a hinged door with a lever handle. Our used-to-be-a-Tom has learned to open them both - but with a lot of noise as he beats on them (tough without thumbs).
Our cat Merlin is indoor-only. He gets anxious pretty much every night as soon as darkness hits, especially if one of us isn’t home yet. At night he lays down next to me and cuddles until I stop petting him, then he goes and runs around the house meowing and jumping from window to window. Sometimes he comes back and sleeps with me. It’s very erratic. I dunno, I guess I’m used to it. He wakes me up every once in a while, and if it’s late his meowing makes it really hard to fall asleep, but for the most part I sleep through it.
ETA: Sorry about your cat, Dung Beetle, I wish I could help. Mine drives me insane sometimes too.
Our three aren’t allowed in the bedroom, and both of us sleep deeply enough that any meowing doesn’t wake us up. All of this “Get up to let him out, get up to let him in, get up to let him out, get up to let him in”…no freakin’ way. They’re CATS, not children. They’ll survive just fine without their slaves for 8 hours or so.
Tabby used to sleep on the end of my bed, every night. The door would be on a crack so she could quietly let herself out and in again. She would only wake me up if Admiration of Prey was required, which was about every other night. It did mean I would have to get out of bed, switch on a light, look at Prey and if it was particularly Impressive, prod it with a pencil. Then fall asleep to the crunching of the skull and sickly smell of blood. Euugh.
I miss Tabby. You can still put a book on the end of my bed and my feet won’t go near it all night. Sometimes I wake with a start and I swear I can feel her jumping onto the bed, and feel something warm pressing into my feet. It’s the most comforting thing I know. I never switch on the light, because she wouldn’t be there. 
(Yeah, sorry, does not help the OP in the slightest. I just miss my Tabby…)
I was actually sort of admiring OP’s steely sense of purpose in not installing a cat door. Because then…the cat has WON. Far better that both of them be miserable.
The SuperKitties all arrived at Casa Scubaqueen as very tiny kittens, so they’ve been trained from an early age that when it’s lights out, they settle in for the night.
Never had an issue with any of them. Maggie sleeps behind my knees, Widget the snuggler will get in under the covers and snuggle herself against my chest, and Turk, my 18-pound bruiser usually sleeps at the foot of the bed out of range of the others. All is good.
You are in the South? What is the max cold temperature for an outdoor cat?
Since I cannot observe it, I start worrying about whether it is alive or dead.
Her Feline Majesty settles down fine (usually on the foot of the bed, sometimes in the headboard or windowsill) once both DH and I are down, or if I’m in bed when he’s not home.
She does seem to have some problems with one human being awake and the other asleep (or trying to be), since she plays “door yo-yo”, going back and forth periodically between humans.
She only gets to go outdoors onto an enclosed patio, so doesn’t usually agitate for outdoors unless an awake human is near the patio door (and it’s occasional then).
Our cats have the run of the rest of the house other than the bedrooms at night. They also can get into the garage via a pet door and from the garage outside if they wish. They are not interested in being in the bedrooms with us and the dogs.
Last couple of years we have been down to 7 cats.
Used to have 4 in the house at night & 3 in the pump house.
Never leave them out at night because of critters that would feed on them.
We moved & being tired of cat hair, ruined furniture, and all that sort of thing + the loss of sleep, we built them a Cat House on the deck, Food, water litter boxes, two story, one on the deck and a basement underneath the deck that in the summertime is where all the litter stuff is. We have a trap door set up so strangers can feed if we are are out of town which prevents escapes. it is really quite magnificent, many perches, windows sleeping boxes all over the walls, ramps to below, a twin bed with 6 separate holes to retreat to & many defensible perches near the ceiling & in corners. Let out by the first one up and the wife serves the wet food at dusk and seldom does anyone balk at going in.
They still get to come inside to visit for short periods in ones & two’s but for the most part, night in the Cat House & day outside. The cat door to the Cat House is always open when they are outside and that is used as their safe place when they want to escape everything from each other or critters or strangers.
When the 4 were in the other house at night, 2 would sleep with me & 2 with the wife. Sometimes she would have to make one fly to get it to settle down. Or to quit running over us what they wanted out before we were up.
They are guard cats, would let us know when strangers or critters were about. When a weapon is in hand, they all stay behind me & watch or run to their safe place. They actually know I am defending them from bad things.
We have very strange cats.
Since even outdoor cats usually find a warm place to sleep it can get pretty cold without being problematic. They also develop winter coats. My family’s cats are all outdoor only cats, and they usually sleep in the stables or other outbuildings, usually with other animals for warmth. The outdoor temperature can drop to well below zero (celsius) without a problem. I wouldn’t know if they had no access to shelter and if they were completely alone with no other animals for warmth though.