Saddened by your husband's choice not to play the game. For men much of life is a game, a competition of sorts, young buck vs old buck. In my last two countries in which I lived, I've learned when you pass a greying road cyclist be ready. Spanish and Japanese older men have cycling jets. They are super fast and very fun-competitive. A sport like cycling can shift between solo and group that will allow his confidence to rebuild and become competitive in the game. The game is life. With that confidence comes increased sex drive, clarity and motivation. Testosterone starts to rock. A diet change, (subtle ) may be helpful Omega s and magnesium increases. sardines avocados. Healthy mind- healthy body AND healthy body - healthy mind. The game is initially one/ won within. Diet and cycling then add pilates or yoga then resistance training. He'll be back on all cylinders in a year and he may well have at least a decade of good years. I with you both the best.