In the end, a year after the borderline sleep apnea test, we optimized my thyroid medication dosage (I had hypothyroidism the whole time but my dose was too low) and I went on a multivitamin, and after a couple of months, the sleep issues that were why I'd gotten that test in the first place went away. And, it's easier to lose weight when my thyroid is properly treated.

I was beating my head against those sleep issues for years, and had multiple doctors sit down and tell me that I probably "just had a high sleep need." In the end, I'm not sure whether it was the thyroid or some vitamin deficiency (before the multivitamin I was on iron, C, and D separately), but it turned out to be very treatable.