I'm going to recommend a "bed tent", which is basically like a modern, temporary, canopy bed. You will be so much warmer at night and only need to heat a small space rather than the entire room. You could make similar tents to hang out in during the day.
Carpets and cushions everywhere is a good idea.
Sharing a bed will also help stay warm at night.
I prefer heated mattress pads to electric blankets. Then you aren't losing heat to the room, it's trapped between the mattress and your duvet. Which, coincidentally, is right where you are.
You can also use these heated pads or blankets outside of your bedroom, by putting them on the floor or couch.
I also strongly recommend getting long john, thermal under garments. Really, this is my #1 recommendation for you. They'll be the best solution all around, because you'll be taking your own heat with you. Before modern heating, people wore padded and quilted clothes (and hats!) inside during winter for a reason. The long underwear will be a tad more discrete, while still helping out with warmth. Remember, when it comes to clothes, socks, and shoes, you actually want them fairly loose. Tight or overly snug cuts off circulation, making you colder. Loose creates an insulating buffer of warm air between you and the clothes, which is how nearly all arctic animals stay warm.
Basically, take a look at some winter historical clothing trends from Victorian times and earlier, or those videos of modern people who live Siberia, and see if you can't copy them. Fingerless knit gloves that go to your elbows, a shawl, and a cap all seem like great ways to stay warm.
If you can do so safely, using something like a pellet stove, or a hot tent camping stove may be an excellent way to heat your main space.
Of course, much of this stuff is expensive. Especially if you don't own any of it already and can't Jerry rig something to work as a substitute or find things used or from charity shops. It may be cheaper to just turn the heat on than to spend a few hundred on new clothes, electric blankets, and personal heaters.
However, you might do the math and discover spending $$$ on a wood stove or alternative heating system will save you significantly in the long run if gas prices remain high, and is therefore worth the cost.