Bogertophis,
Thank you. I really appreciate the "brainstorming."
The only thing that has changed in her enclosure in the past 2 months is humidity dropping from about 60-65% down to 50-55%. I have since, in the past week, upped to 60-65% again.
However, last winter, this wasn't an issue.
The only cleaning solution I use, and always have, is F10SC. I have also, for years, used "Healthy Habitat" to keep the tanks smelling fresh.
Nothing has changed there.
I like the idea of doing a stool sample and bringing her in for bloodwork. I do have a (fairly) local vet I really trust.
We can at least see if something is off, right?
At the moment she's eating, which is a good sign, and I should bring in the sample ASAP. She's due to drop one soon.
EDIT: The healthy habitat is sprayed and wiped up. Not left in the tank.