Je vous la copie en anglais, et je traduis en dessous. Si ça peut vous aider à mieux l'expliquer à vos proches. Je vous mets le lien aussi.
http://www.mssociety.org.uk/about_ms/symptoms/fatigue/what_is_fatigue.html
What is fatigue?
Fatigue is difficult to explain. In MS, it is not just an ordinary tiredness that people might experience after a hard day's work or strenuous exercise. Many describe it as an overwhelming sense of tiredness with no apparent reason. Some people become tired after very little activity, or rarely wake up feeling refreshed in the morning.
How is fatigue different from tiredness?
Fatigue in MS is more than the tiredness everybody feels after exertion. This type of tiredness can still affect you, but fatigue in MS goes beyond that. Some people say they feel like their power plug has suddenly been pulled out – a feeling of complete tiredness that arrives without warning, which can leave just as suddenly. Others notice a constant fatigue that makes everything more of an effort. It may be a frustrating, but tolerable, fatigue that saps your spare energy but lets you work around it. When at its worst, it can be the sort of ongoing exhaustion people get with flu, stopping you from doing even the smallest tasks.
Some people find that when they are fatigued, their limbs feel heavy and it becomes harder to grasp things or to write. Other symptoms, like difficulties with balance, vision or concentration, may also get worse temporarily.