While some girls are more than happy to stick to their guns and NOT be round-heeled little tramps, it's still painful to have the insinuation that the reason *why* you do so is not because of your *convictions*, but because of your *ugliness*.  Equating virginity with being a loser isn't necessarily saying virginity is bad, but is saying you're an ugly, undesirable, person who is only a virgin because NO ONE WILL HAVE YOU.

Carrie seems to DARE someone to tell her she's undesirable.  She knows otherwise -- she's had to wield her hammer enough to know the truth, and is clearly able to shrug it off.  Summer should know better from the number of broken flyswatters she has in the trash, but she's still stung by the specter of being thought undesirable.  Maybe because she's insecure about her not-yet-controlled powers.  Uma...maybe she wrestles with it since she has to live in disguise, and wonders if she will be accepted if her disguise is penetrated.