Lovesick, something that lingers in modern terminology but has a past that stretches much back in time.
Lovesickness was a term used even in the Middle Ages and would refer to both male and females that would be negatively effected (mostly psychologically) by their feelings of love.
In today's society we understand lovesickness to a greater degree and this type of mental state is being explored and its effects on the body and mental health. A real disease that should be treated with importance.