Perhaps it’s just that it’s physical exertion, or exercise, that’s making you tired. If so, your healthcare provider or a physical therapist may be able to help guide you and your wife toward a fitness program that helps you both to feel more energetic and able to be sexual in ways that you desire, without feeling overly tired.
Nutritional needs change with age, too, and it may be that dietary modifications, as suggested by a registered dietician, will be helpful.
Finally, you two both are likely experiencing shifts in your hormones. Sometimes women and men experience discreet periods of time in which their bodies are adjusting to these hormonal balances, and you may feel more easily fatigued in general for a while until you feel more adjusted.
In any case, I’d again recommend checking in with a healthcare provider any time that dramatic changes in sexual functioning are noticed, as sometimes they are signs of changes in health status.
