They arrived before I was expecting them, so I was still in my dressing gown, drinking coffee and eating a custard pie that I'd bought a few days ago on my way back from work. It wasn't a very healthy breakfast, but the crust was already a bit stale and if I didn't eat it now I would have to throw it away. Anyway, I'd been running. I'd puffed my way through five miles on the Heath on a glorious late October morning, sharply cold, but bright too, with soggy brown leaves underfoot. The run, all that pain, balanced out the custard pie. I had planned to paint my toenails, clear the living room a bit and ring up Nick to arrange to meet him for lunch. That way, I could welcome them and then have an excuse to rush off.

But then the bell rang, in three assertive bursts. Before I could answer it, I heard the scrape of a key in the lock. I'd given Kerry a spare key already, but I felt a twinge of resentment. I felt they ought to have let me admit them like guests on their arrival. The scraping went on, and I heard muffled swearing and then some giggles. I stuffed the last morsel of custard pie into my mouth, stood up, tightened the belt on my dressing gown and opened the door, pulling Brendan in with it, holding on to the key that was still in the lock. We were about three inches apart. He was wearing a thick coat that belonged to my father, a long, speckled scarf that looked like one I'd given Troy last Christmas. In his left hand he carried a large nylon bag. I could see pyjamas, a dressing gown, bath foam. His eyes were bright, his dark hair glossy. His mouth looked redder than usual.

'Hi,' I said curtly, standing back to let him in, but he simply took a step towards me, as if he were a partner in some dance, and stood looking down at me. The upturned collar of his coat brushed against my jaw. I felt his breath on my cheek.

'Hey there, Mirrie,' he said. He lifted a thumb and before I could stop him had tenderly wiped a crumb from my upper lip. Then his head bent down, his red lips were on my cheek. I smelt mint, and underneath it something sour.

I turned away and wiped the spot where his lips had been, then retreated further into the hall. Brendan followed. Behind him, Kerry stood, in a bright red duffle coat. Her cheeks were flushed, her fair hair was tied in a little girl's pigtails. She carried a box: bran, herbal tea, vitamin tablets, alfalfa beans, organic elderflower cordial. She had to put the box on the floor before she hugged me.

'Don't close the door,' she said. 'We've got loads more to get out of the car. And Mum and Dad and Troy are bringing the rest over.'

'Don't worry,' said Brendan. 'Just essentials.'

'I'll put some clothes on and then I'll help you with them.'

'Why don't you make us some coffee instead?' said Brendan. 'And we haven't had breakfast yet, have we, Kerry? We were in such a rush.'

'You were in such a rush. I don't know where you get your energy from.'

He smirked, then said, 'Just some toast and jam would be fine. Or do you have tahini?'

'What?'

'Kerry and I are trying to eat healthily.' He put out his large hand and caressed the top of Kerry's head. 'We want to have a long life together, don't we, sweetie?'

'We did this questionnaire on the Internet,' said Kerry. 'You had to say how much you exercised and what you ate, and then it told you when you'd die. I'm going to live until I'm ninety-two. Brendan's going to live to ninety-six.'

'I've only got jam,' I said.

I took my time getting dressed. I sat on my bed for a few moments, breathing deeply, practising being calm. I dressed, brushed my hair unnecessarily, made my bed. The phone rang, but someone picked it up in the other room before I could get to it.

The outside door was still open when I came out of my bedroom, and now my parents and Troy were there as well. There was a small television on one of the chairs. On the kitchen table were a computer with its printer, a portable CD player and a pile of CDs beside it, a bedside lamp with its cord trailing on to the floor. Three large and bulging hold-alls stood by the door. For me, the detail that I found almost horribly intimate was the heap of shoes, his and hers, mixed together. Tennis rackets stood against the wall. An exercise bike blocked the entrance to the bathroom. There was a clutter on the kitchen surfaces: two electric toothbrushes, contact-lens cleansing fluid – did Brendan wear contact lenses, and how had I failed to notice that while I was going out with him? – anti-dandruff shampoo, a make-up bag, another toaster, an electric iron, a framed photograph of Brendan and Kerry sitting on a wooden bench with their arms round each other, piles of holiday brochures, a tangled wind chime that Kerry had had since she was a teenager. How had they managed to accumulate so much so quickly?

I stood for a moment on the threshold of the room and looked at them all. Brendan was grinding coffee beans and Kerry was making toast and jam for everyone, and a comforting burnt smell filled the air. Mum was dressed more casually than I was used to, in an old pair of corduroys and a plaid shirt. Her hair was loose and brushed behind her ears, and for a moment I was taken aback at how carefree she looked. She was carrying a bright bunch of dahlias. Brendan came up to her and put his arm round her and she laughed and leaned against him and held the flowers under his nose. I looked at my father, but he didn't seem to mind in the slightest. He was beaming at the room. He was unshaven and there were circles of sweat under his armpits, jam on his chin.

Troy was sitting on the floor on a folded-up duvet, with his back against the sofa. He was fiddling with a puzzle I'd given him last Thursday, a set of polystyrene shapes which – so it said on the box – fitted together into a cube. I looked at his face as he concentrated. He looked thin and pale and tired. There were bruises under his eyes, as if he'd been crying. But he seemed peaceful as well. Troy is the only person that I know who can be happy and sad at the same time, carrying two kinds of weather round inside him. He slotted in the final shape – yes, it really did make a cube – and gave a smile of satisfaction before taking it apart again. Tenderness rose in my throat and I suddenly wanted to burst into tears.

'Hello, everyone,' I said. I kissed my parents on the cheek and ruffled Troy 's hair.

'Coffee's up,' said Brendan cheerily. 'Afraid I've finished the beans, though.'

'Where do you want to put everything?' I asked Kerry. 'There's nowhere really to hang your clothes.'

'Dad's giving us one of those rails,' she said. 'Just for the smarter stuff and my work clothes. We can stand it behind the sofa. The rest we can just keep in the bags.'

I couldn't manage anything more than a weak, acquiescent shrug. I watched Mum stuffing the dahlias into a tumbler and tried to swallow back a spasm of self-pity. She hadn't given me flowers when she last came round.

'Here we are,' said Brendan. 'Milk, no sugar, right?' He gave a sort of wink, as if he had answered a quiz question correctly.

I sat down next to Troy and watched Kerry put cereal boxes into cupboards. Brendan lifted a heap of books off a wide shelf and inserted the tiny television. 'We can watch it in bed,' he said. 'Is your sofa bed comfy, Mirrie? I've never slept in it.'

'How are you?' I asked Troy. I could see how he was: subdued, all the energy gone, so his face looked blanched and his body limp.

A burst of music filled the room.

'Mozart,' said Brendan, stepping back from the CD player. 'We love Mozart, don't we, Kerry?'

'All right,' Troy said. 'Fine.' He picked up the polystyrene pieces again and started fiddling.

'Here we are, mate.' Brendan squatted down beside him. 'You need blood sugar.' He put his hand under Troy 's chin and lifted up his face. 'You're tired, aren't you. Couldn't sleep?'