Wow, thats the exact same thing that happened to me.
I do have more guy friends then I do girl friends.
So, most of the time I talk to them if stuff is bothering me and they do the same if somethings bothering them. Apparently this created to "close" a bond for them, because 3/4 of my guy friends ended up telling me that they liked me
Now, I had a bf at the time, so I made it perfectly clear to them that I had a bf (they even knew it from the start that I had a bf, but apparently tried blocking that out of there heads). They accepted the fact and knew I would never cheat on my (now ex) bf, but they still flirted with me constantly and then I'd have to remind them over and over again.
Anyways, they are still good friends of mine, but ever since I became single again I've been attacked by a mob of boys that are asking me out. :S
Ooops, I got a bit off topic there. lol. Anyways, just tell them that they need to accept the fact that your not going to cheat on your bf. You just need them as a friend right now and that is important to you.