Your libido is your desire to have sex. And losing it can destroy relationships, especially if it is only one of you who has been experiencing this loss. According to research conducted by La Trobe University, the University of New South Wales, and the University of Sydney, close to 25% of men and 55% of women lacked any interest in sex (1). This startling inequality in loss of libido between both sexes explains why there are so many frustrated partners.