I have an auto-immune issue, most likely MS (have a few of the markers, time will tell). I too have suffered years of extreme fatigue, brain fog, and cognitive issues among a list of other symptoms. I've been off adderall right at a year now- it's been hard but not as hard as I thought it would be. Just recently my energy levels really began improving; it's a long road but don't get discouraged! I personally take Magnesium Citrate in the evenings, I eat foods rich in energy sources, try to get plenty of sunshine and good sleep- the combo does help a lot.
Eventually the adderall no longer gives you productive energy anyways, and the quality of your life gets to the point where sleeping would feel better... In the end, I had worse brain-fog and concentration issues than I ever had without it.
Good luck and read up on the things your body needs and the natural sources where u can get them.