What do you do when your B.F.F.'s crush has a crush on you but you don't want to hurt him 'cause he's your friend but you don't like him like that?
Every single time in my life someone liked me that I knew someone I knew well really liked, I couldn't bring myself to go out with the person. Not that this did me all that much good but it may work a bit of magic in your situation. You could intimate to him that your BFF likes him in that way and that you would not want to hurt her feelings. This may cause him to feel more interest in her, now that he knows but, even if not, if you are subtle enough you will do no-one's honor or heart much damage.
I would tell him how you feel if hes as good of a friend as you say he is then he will understand. Good luck :) u just got advice by a 14yr old