Two things: Fix your diet. The lack of motivation is likely chemistry based, possibly as a result of aging, drinking, or simply poor eating. Regardless, you are what you eat, so fix your diet. Consider volunteer work, or some other group activity involving interaction with other humans in an organized way. Something to bring back purpose and get excited about. A reason to get out of bed in the morning. A project. An Adventure. A mission. Something along these lines. These two things should balance the dopamine issue and help get your mental focus out of the current place, We all need down time, with rest and relaxation, but we also need work and social interaction. We need the stress and up time as well for a proper healthy balance. Without that you atrophy.