The evening, once fizzing with potential, has whittled itself down to a cup of beige, frothy coffee

We're at a party. In a corner, there's a nice, gentle-looking man in a white shirt like a poet. I once had a boyfriend who wore white collarless shirts and wrote brilliant poetry, so I am drawn (yes, still, I confess it) to the type. I wander purposefully in his direction.

He tells me he's a financial journalist. Well, the Poetic Boyfriend also now works in the City, or so I'm told. "But I'm going to take some time off," says this appealingly straightforward man, "and write a novel."

"Oh, you should," I say, because I like him.

We get on to the subject of university. I tell him I failed Oxbridge. He says he got in. (Yes, so did the Poetic Boyfriend.) He goes on to say he knew a girl there who had red hair like mine and who wrote poetry. "Mine's out of a bottle," I say quickly, guiltily.

"So was hers, as it turned out."

He goes on. He was completely in love with her, but she was going out with a friend of his. She was very serious, very bright and some of her poems had actually been published.

"Wow," I say, "How old was she then?"

"Twenty-one."

Then, a few years later, at a dinner party in London, he found himself sitting next to this mousy little short-haired woman with bitten nails and it turned out to be her.

"God," I say, disappointed, "Did she remember you?"

"Well, yeah, but we had nothing to say to each other really. Anyway, a few months later I heard she'd killed herself."

"That's terrible."

"I know." He looks at the ground. Someone tops up his drink.

"So why are you telling me this?" I ask eventually.

He shrugs and smiles, "I don't know."

I'm filled with sudden, panicky gloom. I call Jonathan over. "We have to go," I say, "the babysitter."

"I've had enough," I explain as we hurry out to the car. "There's no one interesting there - do you mind?"

He's perfectly sanguine, reminds me it was my party. We agree that we can't go home. It's only half-past nine and it would be a shocking waste of babysitter. We must eat.

Quickly, I impose conditions. It must be inexpensive, snackish, out of doors and not a pub.

After he's driven to and suggested three places and I've vetoed them all, he asks, "What is it? You're having one of your evenings, aren't you?"

I deny it.

"Will this do?" he slows outside a cafe in Westbourne Grove.

"Sure," I say, then glimpse the neon lights, juke box and men in shirtsleeves drinking lager. "No," I decide, "I just don't like it."

He sighs. "We won't find anything better."

We drive on, everything I see now peppered with my mood. We are almost home, on Lavender Hill, when I finally give a kind of navy-blue bistro place the OK.

There's a table outside. It's oppressively hot, yellow darkness, cars roaring by. "Just a cappuccino." The evening - once fizzing with potential - has somehow whittled itself down to a cup of beige frothy coffee. I think enviously of the babysitter, relaxing in my home.

"I'll bring you a menu," says the young, black-haired waiter, flashing his fillings at us, "Just to look."

I decide that potato skins might be nice. "But without the bacon."

The waiter looks bolshy. "Mushrooms, then?"

"No, really. Just plain. Nothing."

He smoulders off.

It dawns on us that there's no one else in this bistro.

Probably why I chose it - sad. I stifle a yawn.

"Am I keeping you up?" asks Jonathan.

Twenty minutes later, the potato skins come. They are neither plain nor skins, but undercooked jacket potatoes filled with a puddle of seething, microwaved catering cheddar.

As we toy with them, a sun-dressed girl comes running out of the bistro, stumbles past us, hurls herself against the door of a nearby parked car and slumps to the ground. We leap up to help, but a large boyfriend in a Lacoste shirt appears and picks her up, staggers off with her. All four waiters emerge to watch them. There's some excited chatter in French. The boyfriend walks her along the pavement, every so often she dissolves against him.

"Relax," says Jonathan, "What can you do?"

"But is she all right?"

"How do I know?"

Our waiter slouches over: "The skins? They're OK?"

"No," I say, pushing away the plate, "I can't eat them."

"There is a problem?"

"There is actually," I say. "They're horrible."

"Horrible?"

"Yes, awful. They're not skins and there's too much cheese and they're fatty and undercooked and quite disgusting." Though I'm trembling throughout this little speech, I feel instantly better.

"Well, well," says Jonathan, "I've never known you so feisty."

At home, we discover that what we think is one of the kids' toy rubber frogs in the bathroom is actually jumping around. I spit toothpaste all over the floor in shock.

The animal is large and yellowish with black spots. It crouches behind the dirty clothes basket. We can't imagine how a real live frog could have got into our first-floor bathroom. Neither of us wants to touch it but finally we trap it in a large brown paper Habitat carrier bag and - half naked - I creep down to the bottom of the lawn and release it.

It's a sticky night. The frog sits haughtily on the grass and I can tell by the bereft, not-all-that-grateful stare that he's not a frog at all, but some lost soul in disguise - a financial journalist? A pushy waiter? Perhaps even a poet.