Dear Welcome to HCM We understand your concerns I went through your details. You are sure that you have no health issues and health check ups are done every year. You are 46. Everyone has phases of low energy when we just want to veg out on the couch. But prolonged mental and physical fatigue and chronic low energy can be a sign of serious health problems. One of the possible reasons for your low energy, at your age group, could be a significant drop in testosterone levels which can result in a reduced sex drive as well as fatigue. Hypothyroidism, or low levels of thyroid hormone, can also wreak havoc on your energy levels. Your fatigue may be due to a lack of sleep or poor sleep quality. Other possible causes could be depression, anxiety etc. I suggest you to consult a physician for detailed investigation. If you require more of my help in this aspect, please use this URL. http://goo.gl/aYW2pR. Make sure that you include every minute details possible. Hope this answers your query. Available for further clarifications. Good luck. Take care.