Good Afternoon, I Have Talked To My Family Doctor About

Good afternoon, I have talked to my family doctor about this, and he has told me that there is nothing wrong with me physically. I am a 22 year old female. From the age of 15 to 20 years old, I was on Birth Control. I have been off of birth control for a good 2 years now, and my libido has disappeared. I do not have any desire to have sexual intercourse or get aroused enough to self stimulate. I have been sexually active since I was 18 years old and have never had a problem until I turned 21. I have low iron and take supplements for it. I just want to know what would cause this to happen and what kind of things I can do to fix this issue. I am in a committed relationship and have been in one for almost a year and a half. I am sexually interested in my partner, but never feel the desire to explore sexually and it is causing a riff in our relationship. I would just like some information and maybe some answers as to what is going on. If you could help me in any way, it would be greatly appreciated. Regards, Jess.