We are on very similar paths. My wife stays active, with taking daily 1-2 mile walks. She is also on a keto-genic diet- no sugar and low carbs. She is also on a strict supplement regimen to decrease inflammation and boost immune system. Despite all this, the fatigue is real, and she often has to push through it. I know everyone is different, but generally anything he can do to improve his health can be helpful. Fresh, organic, low sugar fruits and veggies; fresh air and sunshine ( wear sunscreen and cover up when undergoing treatment); and something we need to do more of: laugh and love life! Feel free to write back- we're all in this battle together.