BEFORE1Creeping across the threshold, I listen to the silence of the sleeping house. These middle hours, between three and four in the morning when deepest sleep can be reached, make the kitchen seem larger and emptier than in daylight. Different. Although the difference is me. This time I'm saying goodbye.The fragrance of Emma is everywhere, the delicate tang of her green apple perfume. That small wooden box, holding an assortment of tea bags, on the shelf - I'll never again see her bend over it, her hair falling like a veil, sweeping it away as she dithers over her selection. And Luke.

She told me I'll never see him again.There's a large picture on the wall, a print of the Eiffel Tower, a place she visited on her first honeymoon. On the work surface are unwashed plates, remains of their last meal encrusted on the cutlery. I thought she was so neat, but then I never really knew her. Not like you did.Through the kitchen into the large dining room, I move slowly. I don't want to miss a thing. I want to capture the memory of it.

That is where we've sat, Emma and I, cradling hot cups of tea. I notice the red paint on the walls, the white pine of the window seat. On the table is a packet of Silk Cut cigarettes, a box of matches. She's supposed to have given up, but today has been a hard day.I see myself, reflected in a small mirror above the seat. I'm shocked by what my face reveals: there are flushed, red patches on my cheeks and forehead, my eyes are black. Curious, I look closer and see my pupils are fully dilated. I look excited, aroused even.

Momentarily, my heart palpitates; my hands are clammy with sweat. This must be the nervous thrill that burglars feel. But I won't steal anything. Emma was the thief, not me. I've only ever taken one thing from this house: the back door key. Secretly copied, and then returned to its hook. I climb quietly up the stairs, avoiding places I know wouldgroan under my weight. Night-lights illuminate the hall, making me blink.

Emma's door is ajar and I can see into the bedroom. Her curtains are open and the moon is full. Emma sleeps facing the window, the duvet pulled high on her face. Next to her is the bulk of a man, hidden under the bedding. Dominic. Entering their bedroom, I creep up to her foetal shape, studying her perfect ear, her cheek, her blonde hair turned ashen in the half-light, and wonder if I could touch her without her waking. Only inches separate me from her sleeping body. She turns and my muscles tense.

Then I realise that she's moving to the rhythm of troubled dreams. She now lies half facing me and I can see the crease on her brow, the tightness of her mouth. Have I caused that, or are you to blame? Leaving Emma, I walk further along the hall to the nursery, snaking behind the half-closed door. Inside the small room is the beautiful baby boy, asleep in his cot. Luke is surrendered on his back, hands fisted against the blanket, face peacefully fallen, soft skin and round fat cheeks. Usually I just watch him sleep, but tonight that isn't enough. He's familiar with my touch and smell. He stirs when I lift him and I think I hear a voice in the next room.

I pause but hear nothing. His weight is natural to me; I cradle him expertly, one arm along his body, my hand on his thigh. Luke is so peaceful in my arms, head nestled to my chest. I love him, love him fiercely. I hear something in the next room; I freeze, waiting, and the noise becomes louder. Low whispers and then moaning.The repetitive sound of the bed banging against the wall. Careful not to wake Luke, I place him back in his cot and make my way from his room, passing the bedroom where Emma's moans are getting louder, "Yes, yes, yes, yes, yes.

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