Well seams you are doing all the correct things, one good thing is that you have gotten rid of sleep apnea and dibetic, so that is a BIG PLUS, and maybe now that your body is heald of that the weight loss will come now.
See if the protein helps and watch your carbs and salts and any hidden sugars you may be getting. From what I have heard and everyone is different on the loss it just may take you longer with a inactive thyroid.
Good luck and not sure if helps or not but I would like to be at your weight.