4 p.m. Just back from walk round 'garden'. Rebecca kept installing me in conversations with men, then dragging Mark off miles ahead of everyone else. Ended up walking along with Rebecca's nephew: sub-Leonardo DiCaprio lookalike, hunted-looking in an Oxfam overcoat, whom everyone referred to as 'Johnny's boy'.

"I mean, like, I do have a name," he muttered.

"Oh don't be absuuuuuuuuuurd!" I said, pretending to be Rebecca. "What is it?"

He paused, looking embarrassed. "St John."

"Oh." I sympathized.

He laughed and offered me a fag.

"Better not," I said, nodding in Mark's direction.

"Is he your boyfriend or your father?"

He steered me off the path towards a mini lake and lit me a cigarette.

Was v. nice smoking and giggling naughtily. "We'd better go back," I said, stubbing cigarette out under my welly. Others were miles ahead, so we had to run: young and wild and free, in manner of Calvin Klein adverts. When we caught up Mark put his arms round me. "What have you been doing?" he said into my hair. "Smoking like a naughty schoolgirl?"

"I haven't had a cigarette for five years!" tinkled Rebecca.

7 p.m. Mmm. Mmm. Mark just got all horny before supper. Mmmmm.

Midnight. Rebecca made a great fuss of putting me next to "Johnny's boy" at dinner - 'You two are getting on sooooooo well!!' - and herself next to Mark.

They looked perfect together in their black tie. Black tie! As Jude said, was only because Rebecca wanted to show off her figure in Country Casuals gear and evening wear like Miss World entrant. Right on cue she went, "Shall we change into our swimwear now?" and tripped off to change, reappearing minutes later in an immaculately cut black swimsuit, legs up to the chandelier.

"Mark," she said, "would you give me a hand? I need to take the cover off the pool."

Mark looked from her to me worriedly.

"Of course. Yes," he said awkwardly and disappeared after her.

"Are you going to swim?" said the whippersnapper. "Well," I began, "I wouldn't want you to think I'm not a determined and keenly motivated sportswoman, but eleven o'clock at night after a five-course dinner is not my most swimmy time."

We chatted for a while, then I noticed the last of our fellow diners were leaving the room.

"Shall we go and have coffee?" I said, getting up. "Bridget." Suddenly, he lurched drunkenly forward, and started trying to kiss me. The door burst open. Was Rebecca and Mark.

"Oops! Sorry" said Rebecca, and shut the door.

"What do you think you're doing!" I hissed, horrified, at the whippersnapper.

"But ... Rebecca said you told her you really fancied me, and, and..."

"And what?"

"She said you and Mark were in the process of splitting up."

I grabbed the table for support. "Who told her that?"

"She said" - he looked so mortified I felt really sorry for him -"she said Mark did."

12st 4 (probably), alcohol units 3 (since midnight and is only 7 a. m.), cigarettes 100,000 (feels like), calories 3,275, positive thoughts 0, boyfriends: extremely uncertain figure.

When I got back to room, Mark was in the bath so I sat in nightie, planning my defence.

"It was not what you think," I said with tremendous originality, as he emerged.

"No?" he said, whisky in hand. He started striding around in his barrister mode, clad only in a towel. Was unnerving, but unbelievably sexy. "Had you a marble stuck in your throat, perhaps?" he said. "Was "St John" being, rather than the trust-funded teenage layabout he appears, actually a top ear, nose and throat surgeon attempting to extract it with his tongue?"

"No," I said, carefully and thoughtfully. "That is not what it was either."

"Then were you hyperventilating? Was "St John" - having garnered the rudiments of first aid into his marijuanaaddled brain, perhaps from a poster on the wall of the many drug rehab units he has visited in his short and otherwise uneventful life - trying to administer the kiss of life? Or did he simply mistake you for a choice morsel of "skunk" and find himself unable to . . ."

I started to laugh. Then he started laughing too, then we started kissing and one thing led to another and afterwards we fell asleep in each other's arms.

In the morning, woke up all rosy thinking everything was OK but then looked around and saw him already dressed, and knew was not anywhere near OK.

"I can explain," I said, dramatically sitting bolt upright. For a moment we looked at each other and started laughing. But then he turned serious.

"Go on, then."

"It was Rebecca," I said. "St John told me Rebecca told him that I told her I fancied him and..."

"And you believed this bewildering catalogue of Chinese whispers?"

"And that you told her we were..."

"Yes?"

"Splitting up," I said.

Mark sat down and started rubbing his fingers very slowly across his forehead.

"Did you?" I whispered. "Did you say that to Rebecca?"

"No," he said eventually. "I didn't say that to Rebecca, but. . ."

I daren't look at him.

"But maybe we..." he began.

The room started to go blotchy. Hate this about dating.

One minute you're closer to someone than anyone in the whole world, next minute they only need to say the words "time apart', "serious talk" or "maybe you..." and you're never going to see them again and will have to spend the next six months having imaginary conversations in which they beg to come back, and bursting into tears at the sight of their toothbrush.

"Do you want to split up ... ?"

There was a knock at the door. Was Rebecca radiant in dusky pink cashmere. "Last call for breakfast, folks!" she cooed and didn't go.

Ended up breakfasting with mad unwashed hair, while Rebecca swung her shiny mane and served kedgeree.

On the way home we drove in silence while I struggled not to show how I felt or say anything wet. Know from experience how awful it is trying to persuade someone you shouldn't split up when they have already made up their mind, and then you think back over what you said. And feel such an idiot.

"Don't do this!" I wanted to yell when we stopped outside my house. "She's trying to pinch you and it's all a plot. I didn't kiss St John. I love you..."

"Well, bye then," I said dignifiedly, and forced myself to get out of the car.

"Bye," he muttered, not looking at me.

Watched him turn the car round really fast and screechily. As he drove off, I saw him angrily brush his cheek as if he was wiping something away.

15st (combined weight of self and unhappiness), alcohol units 1 - i.e. me, cigarettes 200,000, calories 8,477 (not counting chocolate), theories as to what's going on 447, no. of times changed mind about what to do 448.

3 a.m. Don't know what I would have done without the girls yesterday. Called them instantly after Mark drove off, and they were round within fifteen minutes, never once saying 'I told you so.'

When Shazzer bustled in with armfuls of bottles and carrier bags, barking, "Has he rung?" was like being in ER when Dr Greene arrives.

"No," said Jude, popping a cigarette in my mouth as if it were a thermometer.

"Only a matter of time," said Shaz brightly, unpacking a bottle of Chardonnay, three pizzas, two tubs of HagenDaaz Pralines and Cream and a packet of fun-sized Twixes.

"Yup," said Jude, putting the Pride and Prejudice tape on top of the video, together with Through Love and Loss to Sel Esteem, The rive Stages of Dating Workbook, and How to Heal the Hurt by Hating. "He'll be back."

"Do you think I should call him." I said.

"No!" yelled Shaz.