I know exactly what you are talking about. I had to take an entire year off from school. My concentration, for lack of better term, is kinda like the dog from the movie, "UP". My Neuropsychologist recommended that I be put on meds for the concentration, and it is now being maintained by my primary care physician. It helps some, but I am no where near what the previous me was. It is really hard. I find myself "daydreaming" a ton. I stare off into space, but all of the professionals tell me I should still see improvement, even though I am over my 1 year mark. I know that I push myself too much, do too much and don't take the brain breaks I need to recharge. It's too hard. I want to feel "normal", but who's to say what's normal right? I miss the old me so much sometimes. But I know the new me is the same but just have to do things differently.