How old is your bf?
That's how I was during the first two years with my bf, the only reason it was just the first two years was, because he kept turning me down so much. I'd get so irritated over it that I "died inside", as I put it, and just got used to not getting any.
He was 20 when we started dating and in the last year (he's 24) his sex drive has gone through the roof. I'm not sure if it was, because I made myself less available, or because he was just a late bloomer in the sex drive area.
My best friend has been reading a book called "men are from mars, women are from venus : in the bed room" and they tell you how to make your bf more interested in sex without him
knowing that you're the reason. She's tested it on her bf and she says the methods work great.
So maybe that book could help you?
Good luck!
Christa