Hearing that you will be on a medication for the rest of your life is enough to knock many folks right to their knees, especially if they are young.
I was in my early thirties... and to hear that I had to deal with my thyroid condition NOW (I was in thyroid storm), or die, blew my mind. Then to hear that after my treatment I would have to be on medication for the rest of my life was just too much.
Now, nearly 20 years later, and on a better med and more optimal dose, I look at it much differently.
My thyroid can't produce what my body needs anymore. So I take a replacement hormone. It gives me what my body can't produce, like a vitamin does... so... yes, it's a medication, but it's also like a vitamin, helping my body by giving it what it can't produce enough of on it's own....
I've changed my point of view. I choose to look at it as giving my body a supplement that it needs to improve my health... It's a lot easier to take that way.
The key factor is taking the time, and finding a good doc to work with, to find your own optimal dose. Not just the dose that brings you 'in range' but the correct dose for your body to be well and symptoms to be gone.
Always remember that it's not only the lab results but also your symptoms, or lack there of, that tell you whether or not your dose is correct.