bcfromfl: I agree with your suggestion---great idea to keep warm. I felt better when I added (even more!) layers of clothing during the day, and wrapped up in a blanket when I sat on the couch and read in the evening.
And yes, those warm showers not only help with the heat but also the stiffness.
I even wore a stocking cap inside the house for a few days, as I've heard heat can be lost quickly if your head isn't covered; well, at least they say that when you're outside in the cold, you can lose heat quickly through your head. But it definitely helped me inside the house, too.
Winter is definitely a time to stay warm and cozy, as much as possible. I make sure I have on extra clothing and I wear a winter hat, even if I'm just going outside for a short time, feeding the dog or filling the bird feeder. But I should also mention I'm in a very cold climate, so that's a factor for me, too.
I think staying warm is more important that we think, if we have an autoimmune condition. You made an important point, IMO!