Cast your mind back to your childhood days: is it not true that you had a full tank of energy throughout the day, and thoughts of fatigue only entered your mind when you were told to go to bed. That is the way it should be - having a full day right before retiring for a night of sound and restorative sleep. Now that childhood is but a distant memory, it may be that you have also started to suffer from an ongoing feeling of exhaustion, the bane of a lot of people's lives. It often results in limited quality time with your children and your significant other, and non-participation in activities, because you are too tired. If being tired is impacting your life, the advice that follows could turn things around for you.
Start with a medical examination, to ensure that there are no physiological causes underlying your listlessness. The way you feel may be caused by some foods, so keep track of your food intake and how your energy level is affected. As an example, one of the symptoms of gluten intolerance is exhaustion and this requires a full overhaul of your diet to remedy the problem. It can of course just be a generally unhealthy diet that causes you to feel fatigued all the time and so some changes here can make a huge difference. Any excess weight you carry is a strain and will chew into your available energy, so look into eating more health-consciously daily.
Kids are ceaselessly energetic at least to some extent since they're always in motion and enjoying themselves. Part of the process of aging appears to be that people become less active and do simply nothing quite a lot more than when they were younger. Changing this tendency and moving more, say by going for a walk around the garden, or on the beach, could possibly ease feelings of lethargy. You are likely to encounter internal resistance, because you are feeling tired after all, but shaking this off and getting some exercise may be just what is necessary to get you feeling able and willing again. An option worth looking at is signing up for a fitness class - there are classes for all age groups - and you may even meet quite a few new buddies.
An unnecessary amount of anxiety in your life will leech your energy and could show itself as tiredness even after a night's sleep. It will also make it hard to sleep well, so make learning the art of relaxation an objective. Interestingly, there are forms of exercise which also provide the benefits related to relaxation. Furthermore, you should notice that you are able to sleep better and wake up feeling rejuvenated.
If you follow these ideas you should start to feel less exhausted and have much more energy in your life.