The word disease became a word during medieval times . The word ‘disease’, if you look at it more closely, is dis-ease. Meaning that you are no longer at ease. When we become unwell our energies are out of balance and become chaotic. We are no longer at ease.
I believe that any illness whether that is mental or emotional is there to tell you something. Illness is actually the final result of not paying enough attention to our bodies or our mind and emotions.