Why the low to zero sex drive

Jenny
So basically I'm 27 and have never really had a sex drive at all, why? I met my fiancé 3 years ago the sex was great at first then after about 6 months I was over it and gave no drive at all... I feel bad for my fiancé :( I even saw my doctor about it and she said its normal and most women don't really hit their sex drive potential till their thirties... But listening to friends of mine they have no problems now... Any suggestions... I need help!!!