Excessive weight gain after thyroidectomy

In 2012 I was in a severe car accident which led to CT scans of my entire body. These scans identified what seemed to be "calcium deposits" in the right lobe of mythyroid gland. Over a period of 3-4 years I noticed a slight pressure sensation in my throat. I assumed the doctor telling me of these "calcium deposits" had my mind playing a trick on me. I had not noticed the sensation before I was told something was there.
Soon the pressure sensation got the best of me and finally my wife was convincing enough to make me see a doctor. After two needle biopsies the nodule was scheduled to be removed. The partial thyroidectomy (right lobe) took place August 2016 with an RAI scan to follow soon after. Weigh in before the first surgery was 243 lbs. I am 6'3" so I looked and felt healthy at this weight. Two weeks after the Partial I went to the follow up visit with my surgeon then was diagnosed with Papillary Carcinoma from the lab result findings of the nodule.
A second surgery was scheduled to remove the left lobe of my thyroid October of 2016.  The RAI scan was put off and I was not prescribed medication between surgeries. During this time, two months, my weight increased 19 lbs putting my total weight at 262 lbs. Other negative changes were mood, sleeping habits, energy levels and cognitive function. I was assured by my surgeon that upon completion of the second surgery the prescribed medication would help me restore my body and mind to its former glory. I considered myself to be and strived to be a pleasantly energetic, warm hearted and happy individual. This trait of mine is one that my wife fell in love with and she blessed my life with an abundant reciprocation of passion and love for it.
After the second surgery I was prescribed generic Levothyroxine, 150 mcg daily. I did not feel any improvement on this dose. Weight gain had increased and the negative changes to my mood, sleeping habits, energy levels and cognitive function showed zero improvement. My surgeon increased my dosage to 175 mcg daily. This dose compounded the negative changes tremendously and also caused slurred speech accompanied by moments of great confusion. At this point, depression was consuming my life. I felt like another man looking through my own eyes and the thought of never feeling genuinely happy for the rest of my life was a fear that painted a different, dark, reality in my mind.
I was then sent to an Endocrinologist who adjusted my daily Levothyroxine intake to 150 mcg Monday-Friday and 225 mcg Saturday-Sunday. This adjustment improved some of the negative changes. After three more visits to my Endocrinologist and multiple blood panels she prescribed me 5 mcg of Cytomel daily to take with my current dosage of Levothyroxine. Just a few days after taking these two medications together my wife noticed positive increases in my mood and cognitive function. After being on this combination for a few months I have experienced tremendous positive changes and am starting to feel like my normal self. Almost. The largest impact on my life is weight gain and my health is in jeopardy. I may have possession of my mind and happiness but my body has suffered. See, in a short 14 months I have gained 83 lbs. putting my total body weight at 326 lbs. I do not look or feel healthy. Reading many posts and forum threads the weight gain is a troublesome effect most people have after full Thyroidectomy. I see people speak of dieting and exercise with no continuation or follow up with results. Is there anyone out there that has a proven method for trimming off all this excess weight without an athletes daily gym routine? Or am I missing something from a medical stand point?