Awww, don't feel bad, I feel the same way. Nobody asked me out before either. I still think that we're still to young( I'm 13 too). The grade eights in my school all have boyfriends, well, some of them. In my school, I think its pretty hard to get into a relationship, people are too shy to ask and stuff. Even at school dances, only the older kids dance. ONLY.
Anyways, I sill think we're too young. I'm going to wait until at least I'm 14 or 15 to start dating, if I get a boyfriend. But now, it doesn't matter, because we're still young, and I'm positive that there are some guys out there that like you. But I know how you feel, when all your friends ask you why you haven't dated before. I know it must be very embarrassing. I don't know why, but I hate when people ask me if I had a boyfriend before, it just annoys me. Just ignore them if they ask why, like how do you tell them exactly why.
I'm glad that you decided to tell us your problems, just remember, we're always here for you
*hugs*