I have Thyroid Problems, and feel like all my energy is gone. Can’t Loose Weight. Help?

I have an inactive Thyroid, taking synthroid and it helps very little. I feel so tierd all the time and have no desire to do the things I know I need to do. Nothing seems to matter to me anylonger except my 2 grandsons, 6yrs and 2yrs. I am 58 and shouldn’t feel this bad all the time. I ache all over. And this is a daily thing. Is there anything I can do for this, I am loosing special moments with my grandchildren. And it is causing other problems, I can’t remember things. I have always handled all business and household business myself, and I can’t seem to do any of it anylonger.This is causing searious problems for me and my family. Appreciate any advise from someone who has been where I am now. Thanks so much.