"My remaining symptoms? Depression, emotional numbness, fatigue, occasional insomnia and anxiety, no libido, low body temperature, irritability, little desire to be around people, lack of motivation. "
I have all of those except the low libido. That is one symptom I wish I had. DHEA might increase libido, although women should probably just take a small dose of this, perhaps just 10 mg a day to start. This article links low libido to hypothyroidism.
Two herbs you should look into are Schisandra and Dong Quai.
I still think that 200 mcg a day of selenium might help with your thyroid problem, as selenium is necessary for conversion of T4 to T3, and mercury binds with selenium and makes it unavailable. I am glad you are taking the Lugol's solution. How much are you taking? If you are very iodine deficient, it may take a few weeks until you notice some results from it. It seems like my body temperature is closer to normal now after a few weeks of iodine supplementation. Heat intolerance also seems to be linked with thyroid dysfunction.
You are only on day 5 off sugar? I thought you were off sugar for a long time. Try to cut down on caffeine, as that contributes to heat intollerance. I am now down to one cup of coffee a day.