Wow. I just say "no thankyou" if I'm not into someone, but then, I'm a married dude. Rejecting people is really easy for me. Most men, actually. Women get the short end of the stick here because they live in a house of cards.

On one hand, women have a hundred times the opportunities for sex and relationships that men do. It's really easy to find a man that's interested. Maybe not a man you're definitely into, but very easy to find a man who's willing. It's not as easy for men (which is why some assholes get so pushy and butt-hurt when they get turned down -- it's not like they can go find some other woman easily).

But on the other hand, there's this unspoken, tense situation for women that's constantly there: Men, on the average, are stronger than women. The only reason women have any power at all and can walk from point A to point B safely is because most men play along. But any particular man at any time could just say screw it and quit playing along. It doesn't happen often, but there's this unspoken tension that at any given time, the man you're staring at could quit playing along and take your power away.

Which is why instead of "no thankyou", some women expel this tirade of bitterness. It's scary being a woman, because "no thankyou" only works if the man plays along.