A common cause for the decline in sex drive in women is menopause. Sex during and after menopause can be horrific for many women. Having to deal with mood swings, hot flashes, depression, and vaginal dryness can make sex very painful and for this reason many menopausal women would rather not engage in it.
During menopause, the sex drive can drop to very low levels. Many women find they don't think about sex at all. For others who still engage in sex, sex can be quite difficult to enjoying and often times these women lose interest in it altogether. The decrease in libido is thought to be due to the decline in the estrogen, progesterone, and testosterone levels during menopause. Each of these hormones plays a specific role in a woman’s sex drive. While estrogen helps heighten sensitivity during sexual intercourse, testosterone lubricates the vagina. Progesterone, on the other hand, is basically the sex hormone that excites the libido of a woman. i have read from this site http://premenstrualsyndromesupport.com/everything-about-women%27s-aging-sex-drive.php...that there are lots of reasons that causes lose interest in sex...some are fatigue, mood swings and depression.