My bum stinks!

Ok, so i have this problem, where my bumhole stinks! I am a women and to have a bumhole that smells like a dead fish is not attractive! A few weeks ago my boyfriend wanted to give me anal, but i had to refuse. I think hes smelt it a few times during sex but just not mentioned it because he knows i will be embarrased. I am embarrased about it, so i dont know what to do. Ive tryed to go to the doctors but they have told me its nothing and it should go away. But that was months back! Ive tryed creams and ointments that could help the smell, but they havent worked. Its ruining my life and i dont know what to do...please help :/