‘What, and miss your party? Not for the world.’

She’s dressed in a white sequined Moschino number. Very ice maiden meets LA débutante. I couldn’t have chosen better myself. She’s obviously taken great care and spent her dowry.

‘Are you getting changed?’ she nags.

‘I haven’t thought about it.’ Fi pulls a face. ‘OK, OK, I’ll look through my filing cabinet. There’s bound to be something to wear in there.’ I know she’s worked hard and wants everyone to appreciate her effort by making an effort.

Fi has plumped for a theme of black and white. She said this was largely to do with the invitations being sent out so late in the day; the guests are mostly media luvvies, and a dress code stipulating one or other of these colours won’t cause any problems. Despite the brief, I emerge from the loos, fifteen minutes later, with freshly applied lipstick and a scarlet Johanna Hehir dress. It’s clingy, flowery and feminine. I believe in the importance of an entrance.

I follow the noise of laughter and clinking glasses and the heady perfume of fat waxy lilies up to the roof terrace where we are holding the jamboree. The lift parts and my first impression is top. Waiters, dressed in Paul Smith, carry trays of champagne. There are dozens of lanterns and fairy lights everywhere and whilst it’s still too light and warm for them to be anything more than decorative, they are certainly that. There are sculptures of huge chess pieces scattered about. I’m not sure what their original purpose was intended to be but they are being used as giant ashtrays and bar stools. There are luxurious, white, faux-fur rugs hanging on the walls. The food looks exquisite; it also follows the theme of black and white – piles of scrumptious-looking caviar followed by attractive miniature summer puddings, made entirely with blackberries and served with heavy dollops of double cream. Fi has done the correct thing by serving small amounts of delicious-looking food. It barely matters what it tastes like, as most of the guests would rather polish the shoes of the entire British army than consume unanticipated calories. Still, the media luvvies look the part; as my mother would prosaically say, ‘They scrub up well.’ The room is awash with every label in the alphabet, from Armani to Versace.

The effect is magical.

I help myself to a glass of champagne and look for someone useful to talk to. Fi prevents this by hurtling towards me.

‘OhmygodOhmygod,’ she screams.

‘What? Have I lipstick on my teeth?’ I ask, rubbing my teeth with my finger. As I do so I notice there’s soap stuck in my engagement ring; I take it off and start to gouge it out with my fingernail. Something is certainly upsetting Fi. She looks as though she is hyperventilating.

‘I am so sorry. I can’t think how it happened. We used mail merge. His name must have been on the wrong list,’ she gabbles.

‘Whose name?’ I ask. But Fi can’t answer because she’s staring at something behind me. She looks like a rabbit terrified and trapped in the headlights of an oncoming truck. I turn.

I’m the rabbit.

‘Darren? Darren?’ I can hardly believe it is him. For months I’ve been trying to convince myself that seeing Darren again would be the worst thing that could possibly happen to me, but now I’m actually facing him, I have to admit it feels like the best. The crowds around us dwindle and there’s just the two of us. Which is a nightmare because my tongue is cleaving to the roof of my mouth and I can’t think of anything at all suitable to say. I slip my ring in my pocket.

He’s breathtaking. He’s everything I’ve been imagining and remembering for the last six months, but more.

I’m expecting an onslaught of anger and recriminations and try to head them off by putting us on a polite and formal note immediately.

‘Are you here for the party?’ Then I shoot myself. Or at least that would be a suitable penalty for such a banal conversation starter but I don’t have a gun handy.

‘I suppose I am,’ he says, half grinning and wincing at the same time. My La Perla hiccups.

‘Good, good. I’m so pleased.’ I like this sentence more. It is at once honest and straightforward. Honesty and the ability to be straightforward are things I know Darren admires. ‘I didn’t expect to see you here,’ I rush to clarify. ‘Not that I invited you.’ That sounds awful. ‘I mean. I didn’t send out the invites.’ He looks confused. ‘Well, it’s not your sort of thing, is it?’ My voice finally falters and then draws to a halt. I suspect we are both relieved.

We stand awkwardly watching other people enjoy themselves, until eventually Darren asks, ‘Will Trixxie be coming along?’

I’m crushed. He’s here for Trixxie. Not me.

Not that he could be here for me. Not after I’ve ignored him for six months.

Nor should I want him to be. I’m engaged to Josh and I don’t do casual sex any more. I try to tell myself that my jealousy is a lazy hangover from my other life.

‘I don’t know. I don’t think even Fi knows who she’s invited, judging by the look of confusion on her face when she saw you. If Trixxie is coming she’ll be late,’ I add sulkily. He’s grinning. No sign of disappointment that Trixxie may not appear. Maybe he just thought of her because I was behaving like an incompetent. I add, ‘It’s quite a select gathering.’

‘I’m touched.’

In case he thinks I am, I clarify, ‘And your name got on the list by mistake. A fault with mail-merging the wrong list.’

‘Ha,’ he guffaws. He actually throws his head back and laughs out loud. As ever, I’m not sure if he’s laughing at me or with me. But I don’t care. I just like hearing his laughter. It cheers me. It is definitely the most exhilarating sound I’ve ever heard.

‘You don’t change, do you?’ he asks.

In fact, I do. I have. And if I tell him I’m engaged that would prove it.

My mouth is welded together.

I wait for him to walk away but he doesn’t. Instead he asks, ‘What did you think about that article on Ian Schrager’s latest hotel?’

‘Sorry?’

‘Or the one on the Balinese spas?’ He is referring to the web pages he’s e-mailed to me. The one on the spas was the last one he sent, nine weeks ago. ‘It’s just you never said.’ Darren stares at me and his stare could shatter granite. Every one of his e-mails had been selected with peculiar care. They always referred back to some conversation we’d had in the halcyon period. The two weeks when we behaved as a couple. The two weeks when we were a couple.

I cough up my voice. ‘I – I often visit the Starsky and Hutch site.’ The side of his mouth twitches a fraction. ‘And the one about historical Oscars. In fact all the articles were interesting.’

Darren nods. It’s a tight, tense nod. Hardly perceptible. I need a drink. I daren’t move towards a champagne tray, in case Darren takes the opportunity to leave, so instead I flag down a waiter and insist he fetches us a couple of glasses.

Darren accepts the glass but he doesn’t look comfortable.

‘What should we toast to?’ he asks.

I consider suggesting that we could toast to my engagement.

But I don’t.

‘To, er, you. You look well. Let’s toast to you,’ I suggest.

‘No. That would be far too unchivalrous. How about to you? You’re always well, aren’t you?’ I don’t quite know how to answer that. He doesn’t sound 100 per cent genuine. I shake my head warily.

‘Proposing we toast to us seems a bit off key,’ he snipes.

‘Suppose so,’ I mutter reluctantly.

‘I’ve got it. Here’s to Sex with an Ex.’

I catch his eye. ‘Er, Sex with an Ex,’ I mutter, because really, here’s to it. But can Darren mean that? He can’t be toasting the programme. He loathes the programme. So does he mean a genuine ex? Me? Is he flirting? I clink my glass. I hope he’s flirting.

I can’t believe my luck. I keep expecting him to make his excuses and go and talk to someone else but he doesn’t leave my side. Instead he attentively fills my glass, fetches me caviar, walks the room with me, allows me to introduce him to innumerable colleagues. He stands outside with me when I feel overwhelmed by the heaving throng and then he dances with me when I feel so happy that all I want to do is fling my body in random, jerky movements to the thumping bass. He stays right by me, carefully watching my every action, listening to my conversations with other people, and he seems to be happy to do this. We both behave as though we’ve seen each other every day for the last six months. Darren doesn’t publicly rebuke me for my terse note and sudden disappearance; he doesn’t refer to a single aspect of my despicable and undoubtedly confusing behaviour. I don’t know what to make of this. Am I so insignificant to him that he can’t even summon up the curiosity to ask me why I behaved so strangely? But if that is the case, why spend the evening with me? If I were more trusting, the only conclusion I could draw is that he wants answers but he won’t embarrass me in front of my colleagues by demanding them. He’s too polite. He cares too much.

Believing that he cares at all sends me into a state of near hysteria.

Throughout the evening he is a delight. He charms and amuses everyone. He chats to Debs, Di and Jaki, who are enraptured with his good looks and general affability. Trixxie stands speechless, with her jaw hanging open as she listens to his theories on why women find Robson Green irresistible.

‘She’s literally mesmerized by you,’ I tease him.

‘No, it’s drugs,’ he grins modestly.

I watch as Darren works his sorcery on the celebs who normally make it a rule not to be impressed by or even civil to anyone other than their next pay cheque. He grips the ‘gentlemen’ of the press by quoting their own articles back to them and having an informed opinion on the broadest range of subjects – anything from the ins and outs of India’s election systems to the GDP per capita in Japan. He even impresses Bale, who, desperate to meet Darren, follows him around the room and contrives to collide in the urinals. In our two weeks together I’d painted a bleak, but accurate, picture of Bale which must now be colouring Darren’s judgement. Whilst happy to talk to everyone from the bar staff to the chairman, Darren steadfastly avoids Bale and won’t treat him to more than a casual wave across the room. And whilst everyone is captivated by Darren, I am bewitched. He is just as funny and interesting and polite and sincere as I remembered.