THYROID Dear Doctor, Kindly Go Through This With Patience And

Question: THYROID
Dear Doctor, Kindly go through this with patience and give me your valuable advise.
I am 78 year old and my wife is 70 year old. We both are diabetic. I had diabetes in the year 1912 (NDDM) and my wife in 2005 (NDDM).Right from the beginning the diabetes is well under control for both of us.Self HBA1 c 6.4 % and my wife 5.7%.This is our medical history.
Now I am coming in to the main subject.
Casually my wife got her blood test for TSH without consulting my physician in the year 2011 .The lab report shown 4.7 without any symptoms. She went to our physician and shown the result.Till then she has never consulted the doc on this issue because she has never experience any symptoms regarding the thyroid.
He immediatly prescribed 25 mcg thyronorm once a day in the early morning stating tht she has subclinical hypothyroidsm , even the level is well below the normal (0.35 to 5.5)
Since then she is taking the thyronorm and increasing and decreasing the dosage without consulting the doctor, because she has never experienced any symptoms. Nearly 9 years have passed.She is now taking 50 mcg and the level is 2.2%. She is taking the medicine based on the lab reports only .The T3 and T4 are also very well normal. She is not either obese or lean. Her dosage range from 25 mcg to 100 mcg.No swelling in the neck at any time. No unexplained weight gain.No horse voice. No lethargy .No rapid pulse rate. My cholesterol is 129.
Her TSH ranged from 2011 to 2019 between 1.2 to 5.9 (2013).
Like wise I have also undergone the lab test for TSH once casually in the year 2011 without consulting the doctor , and it was 10.1. I have also took it to my physician and he prescribed 25 mcg stating that I have subclinical hypothyroidsm. Like my wife I am also increasing or decreasing the dosage of thyronorm based on ;lab report . I have never consulted the doctor since I have never had any symptoms. Now the present level is 1.7 The T3 and T 4 are also normal.I am not obese and asymptomatic . I am taking 50 mcg now.The levels from 2011 to date ranged between 10.1 to 0.3 % and the dosage ranged from 25 mcg to 100 mcg.No swelling in the neck at any time. No unexplained weight gain.No hoarse voice. No rapid pulse rate.My cholesterol level now is 111.
All these years we have never given any serious thought to this. Now we wish to have a serious consultation and wants to put a fullstop for this medicine of course by tapering the dosage.
Kindly give your opinion in this regard.

Doctorwhat i understood is when tsh level is above normal we ha e to give low thyronorm dosage and if tsh level is low ee have to give higher dosage.am i right or have i gone wrong?