20st 12 (feel like, compared to Rebecca), no. of pains in back from vile foam mattress 9, no. of thoughts involving Rebecca and natural disasters, electrical fires, floods, and professional killers: large, but proportionate.

Rebecca's house, Gloucestershire. In horrible guest cottage. Why did I come here? Why? Why? Sharon and I left it quite late and so arrived ten minutes before dinner. This did not go down very well with Rebecca, who trilled, 'Oh, we'd almost given you up for lost!' in manner of Mum or Una Alconbury.

We were staying in a servants' cottage, which I decided was good as no danger of bumping into Mark in corridors, until we got into it: is all painted green with foam rubber single beds and Formica headboards, in sharp contrast to last time was here, staying in lovely hotel-style room with own bathroom.

"Typical Rebecca," grumbled Sharon. "Singletons are second-class citizens. Rub it in."

We teetered in late for dinner, feeling like a pair of garish divorcees because we'd put our make-up on so quickly. Dining room looked as breathtakingly grand as ever, with a huge inglenook fireplace at the end and twenty people sitting round an ancient oak dining table lit by silver candelabras and festooned with flower arrangements.

Mark was at the head of the table, sitting between Rebecca and Louise Barton-Foster and deep in conversation.

Rebecca appeared not to notice we'd come in. We stood staring awkwardly at the table till Giles Benwick bellowed, "Bridget! Over here!"

I was put between Giles and Magda's Jeremy, who seemed to have forgotten I ever went out with Mark Darcy and launched things off by going, "So! Looks like Darcy's gone for your friend Rebecca, then. Funny because there was this bit of totty, Heather someone, friend of Barky Thompson's, who seemed to be fancying a bit of a crack at the old bugger."

The fact that Mark and Rebecca were in earshot had clearly escaped Jeremy, but not me. I was trying to concentrate on his conversation and not listen to theirs, which had turned to a villa holiday Rebecca was organizing in Tuscany in August with Mark - as seemed to be the assumption - to which everybody simply must come, except presumably me and Shaz.

"What's that, Rebecca?" bellowed some terrible hooray I vaguely remembered from the skiing. Everyone looked at the fireplace where a new-looking family crest was engraved with the motto 'Per Determinam ad Victoriam'. It was quite strange to have a crest since Rebecca's family are not members of the aristocracy but something big in estate agents Knight, Frank and Rutley.

"Per Determinam ad Victoriam?" roared the hooray, "Through ruthlessness to victory. That's our Rebecca for you."

There was a huge roar of laughter and Shazzer and I exchanged a gleeful little look.

"Actually it's through determination to success," said Rebecca icily. Glanced up at Mark, a trace of a smile just disappearing behind his hand.

Somehow got through the meal, listening to Giles talking very slowly and analytically about his wife and tried to keep my mind away from Mark's end of the table by sharing my self-help book knowledge.

Was desperate to get off to bed and escape the whole painful nightmare, but we all had to go through to the big room for dancing.

I started looking through the CD collection to distract me from the sight of Rebecca slowly rotating Mark round the floor, her arms round his neck, eyes darting contentedly round the room. I felt sick, but I wasn't going to show it.

"Oh, for God's sake, Bridget. Have some common sense," said Sharon, barging up to the CDs, removing 'Jesus to a Child' and putting some frenetic garage acid medley on instead. She strode on to the floor, swept Mark away from Rebecca and started dancing with him. Actually Mark was quite funny, laughing at Shazzer's attempts to make him trendy. Rebecca looked as though she had eaten a tirarmisu and only just checked the fat units.

Suddenly Giles Benwick grabbed hold of me and started to rock and roll me wildly, so I found myself being flung around the room with a fixed grin on my face, head bouncing up and down like a rag doll being shagged.

After that I literally couldn't stand it any longer. "I'm going to have to go," I whispered to Giles.

"I know," he said conspiratorially. "Shall I walk you back to the cottage?"

Managed to put him off and ended up teetering across the gravel in my Pied a'Terre slingbacks and sinking gratefully into even this ludicrously uncomfortable bed. Mark is probably at this moment getting into bed with Rebecca. Wish I was anywhere else but here: the Kettering Rotary summer fete, the Sit Up Britain morning meeting, the gym. But is own fault. I decided to come.

22st 10, alcohol units 0, cigarettes 12 (all secret), People rescued from water accidents 1, people who shouldn't have been rescued from said water accidents but left in water to go all wrinkly 1.

Bizarre, thought-provoking day.

After breakfast, I decided to escape and wandered round the water garden, which was quite pretty, with shallow rivulets between grassy banks and under little stone bridges, surrounded by a hedge with all the fields beyond. I sat down on a stone bridge, looking at the stream, and thinking how it all didn't matter because there would always be nature, and then I heard voices approaching behind the hedge.

"... Worst driver in the world ... Mother's constantly ... correct him but ... no concept ... of steering accuracy. He lost his no-claims bonus forty-five years ago and never got it back since." It was Mark. "If I was my mother I'd refuse to go in the car with him, but they won't be parted. It's rather endearing."

"Oh, I love that!" Rebecca. "If I were married to someone I really loved I would want to be with them constantly."

"Would you?" he said eagerly. Then he went on. "I think, as you get older, then ... the danger is if you've been single for a time, you get so locked into a network of friends - this is particularly true of women - that it hardly leaves room for a man in their lives, emotionally as much as anything because their friends and their views are their first point of reference."

"Oh, I quite agree. For me, of course I love my friends, but they're not top of my list of priorities."

You're telling me, I thought. There was silence, then Mark burst out again.

"This self-help book nonsense - all these mythical rules of conduct you're presumed to be following. And you just know every move you make is being dissected by a committee of girlfriends according to some breathtakingly arbitrary code made up of Buddhism Today, Venus and Buddha Have a Shag and the Koran. You end up feeling like some laboratory mouse with an ear on its back!"

I clutched my book, heart pounding. Surely this couldn't be how he saw what had happened with me?

But Rebecca was off on one again. "Oh, I quite agree," she gushed. "I have no time for all that stuff. If I decide I love someone then nothing will stand in my way. Nothing, Not friends, not theories. I just follow my instincts, follow my heart," she said in new simpery voice, like a flower girl-child of nature.

"I respect you for that," said Mark quietly. "A woman must know what she believes in, otherwise how can you believe in her yourself?"

"And trust her man above all else," said Rebecca in yet another voice, resonant and breath-controlled, like an affected actress doing Shakespeare.

Then there was an excruciating silence. I was dying, dying frozen to the spot, assuming they were kissing.

"Of course I said all this to Jude," Rebecca started up again. "She was so concerned about everything Bridget and Sharon had told her about not marrying Richard - he's such a great guy - and I just said, 'Jude, follow your heart."'