The Good News- You have a brain! I know it is always reassuring when I see evidence that my brain is still there
Brains will atrophy for a variety of reasons which can include aging. You might discuss this with your doctor.
I found the past three and a half years I did much better with my daily brain workout as I home schooled my little boy. Now I am chaperoning him on campus each day. I still get a cognitive workout as we discuss his classes. I also read many books, newspapers, and college texts. Will this help brain atrophy?? I do not know, but I hope to keep it up until my last breath! I too have "fuzzy days" and I know that my son's learning will soon pass my comprehension, but in each day I find a measured blessing from God and I am happy that my cup runs over. I hope you will shake off the worries and step forward with confidence.
Each day starts anew. What we do with that day determines our daily life. On the worst of days, I choose to push forward and obtain my "worst day" goal. Set goals you can obtain and then push the bar higher. On bad days, lower the bar, but not too low. I remember an especially bad day when I could only read a few pages before fatigue closed my eyes...still, I read a few pages and I was able to do one thing.
Stay strong, you are in my prayers.