I've been thinking about this for a few days...as much as it might be a little freaky, PBR, for a man to get huge, it's freakier for a woman.
Muscularity has always been an ideal for men. BBing just takes what's "normal" for a man and takes it to the extreme.
Female bbers, on the other hand, face more opposition, I think. The traditional female ideal has been one of softness, of weakness. Hell, not that long ago, the look caused by TB was considered romantic: pale skin, big, dark eyes, and a languid disposition. (I wouldn't be surprised if some men thought the idea of a woman with a short life expectancy was a good thing, even...not too much of a commitment!)
Well, obviously things change. But a very muscular woman remains an oddity in most folks' minds. We threaten weak men, and women wonder if we're lesbians after their flaccid asses. (As if! If I wanted a woman, I'd want a fit woman!)
Quadsweep's Sister, I say: fuck what others think. Emerson said that a wise man (read: person) maintains an independence of the good opinions of others. That's what I try to do.
Besides, like Aesop's fable with the father, son and donkey on the way to the market illustrates, you just can't please everyone. So please yourself. If folks don't like it, well...you don't need those kind of people as friends, anyway.