bleeding for everyday for three years

Hi my name is mull mull i have been bleeding for three years and my doctors given up on me as he thinks that theres nothing wrong. I have had ultra sounds, blood tests, bio's, been to 20 ginos. I been married for two years and i know my husban is faithful to me as we work together and live together we have a business and thats our life... I have now got to the stage where i wake up every morning wanting to be sick but can't throw up. i'm not on any birth control and im not pregnant. I think and pray to myself every day please stop. Im not overweight so i have no idea. in the past three months since the doctors have given up im feeling so down in the dump is there any one out there that has or had the same problem please help..... im 21