"Well," interrupts Sophie, "If you're so worried about being out in the streets at night, why don't you just take a taxi?" She sips her chardonnay, checks her manicure and looks round the table.

"No, seriously," she says, "I know you have to wait sometimes, but it's the only sensible thing to do."

Sophie, you must understand, went to university. My main memory of her is that she was one of those people who always ran their fingernail over invitations to see if they were engraved. And her legendary student advice: "there's no point buying cheap shoes, they don't last"; "no one can tell the difference between Marks and Spencer and home-made"; "it's better to stay in a decent hotel than fly first class"; "you can see so much better in the stalls".

She lived in a different world from me back then and, fortunately, those worlds don't clash much now. But you can't veto other people's hen party guests just because they're stupid.

Babs, who hasn't met Sophie before, thinks it's worth protesting.

"I'm a primary school teacher," she says. "I can't afford to take taxis everywhere."

Sophie rolls her eyes, rattles her bracelets.

"That," she proclaims, from the lofty height of someone who married a banker at 22, "is the trouble with this country. Moan, moan, moan. If you're not happy, get another job".

"But Sophie, I like teaching. I trained to do it. I make a contribution."

"Oh, God, politics," says Sophie. "I hate politics."

She turns to her neighbour, and returns to her dissertation on how she got back down to her pre-birth weight in a month. "It was easy," she says. "You should try it. High protein, low fat: prawns and things, and only green vegetables. And absolutely no alcohol apart from champagne ..."

The rest of us continue from where she rejected us. I ask Babs where she teaches, and she starts describing her state school in Camden. She's been there five years. I lasted two as a teacher myself.

"Why did you leave?"

"Loads of reasons. The money, the staff room, the parents."

Babs rolls her eyes. "Oh, I know," she says. "Parents' evenings are the bane of my life. Trying to talk about about respect and manners to someone whose idea of formal dress is a matching shell suit ..."

Sophie whirls back. "Chanel suit?" she says. "Hopeless. Haven't bought one in years. Donna Karan's the only thing ..."