I'm not Shelley and I can't tell you much about the thyroid, but I can tell you that your poorly functioning liver is probably the root cause of your candida.
Poor liver function = mal-digestion = Putrificaiton of food in intestines = candida
which in turn will supress liver-function due to all the toxins candida releases.
The only way to permanently break this vicious circle is to restore the liver function with flushes and herbs.