I am walking down the corridor in my flat. The monster is at my throat, claw stuck fast. I cannot eat. I can scarcely breathe. It is 10 months since I was diagnosed with severe clinical depression, months without beginning or end. Time moves like treacle, running thick and heavy through my days.

I hate this flat. It is beautiful, a mansion flat two floors up with high ceilings and ornate fireplaces; but I know that behind the facade, the walls are running with tears. My tears. Pain has seeped into the plaster.

The flat is laid out in two parts, with a long, narrow corridor connecting the two. At one end there is a large, light-filled sitting room and two bedrooms, Molly’s and mine. The rooms are painted cream and white, testament to an earlier time when I tried to decorate myself out of the dark.

My bedroom is small; kept dark by the linen curtains which I made myself and which I keep shut fast against the day. The white duvet cover has scorch marks in it from the cigarettes I smoke in the dead of night when I am dragged from sleep by some unknown, unseen terror, but too dazed with sleeping pills to know what I am doing.

At the other end of the corridor is the kitchen, and my study, where I rarely go. Sometimes I venture in to sit at my computer in front of the dead, blank screen and flick idly through my piles of books. They are dusty and sad, with a long neglected air. I never stay in there for long.

The kitchen is huge and half finished. There are no units, just a few rudimentary cupboards; the fridge is ancient and most of the shelves have collapsed. The hot water tap is stuck fast. I haven’t the energy to call a plumber. I’m not sure that I even know how.

Sometimes this strikes me as odd. As a magazine editor, I used to head up a staff of 40 and handle a budget of millions. Now, I can’t even call a plumber, so I wash up by boiling a kettle for hot water.

As I walk down the corridor, I keep my hands pressed to the wall because I am shaking so hard I can hardly stand. The next thing I know, I am flat on the ground, my face pressed into the carpet. I think, how did this happen? Did I stumble and fall? I have no recollection of it. I tear at my throat, uselessly, trying to pull the monster away. I think, I will die now. There is no other way.

Or, just one. Vodka. When the pain is this bad, I know of no better anaesthetic than vodka. No prescribed tranquilliser comes close.

I stumble to my feet and inch along the corridor, hands pressed fast to the wall to steady myself, and knock a framed photograph askew. I collect black-and-white photographs. There are Norman Parkinson’s women, serene, glacial and unaccountably chic, and Andrew Macpherson’s modern girls, smiling and sexy. There is Matt Dillon, from an early photo shoot I did with him on Vogue. And there is Bruce Weber, photographer, filming in Cannes.

I love them. They are beautiful. Now, I knock past them clumsily, as if they do not matter.

My kitchen looks peculiar, as if it is both intensely familiar yet a room I scarcely know. I scrabble in the freezer, pull out a bottle of ice-cold vodka and pour a measure into a glass. My hands are shaking badly. Some of the vodka spills on the wooden table, which I used to polish weekly, with beeswax and soft cloths. I leave the wet puddle, allow the ethanol to eat into the wood. I haven’t the energy to find a cloth.

The vodka burns at my throat but, gradually, the heat penetrates and the claw lessens its grip a little. What time is it? A little after 10 in the morning. I try to remember what 10 in the morning means, how it feels. But I cannot. Time means nothing to me any more. I stagger back to bed, and try to sleep. Try to pass out. I don’t want sleep. I want oblivion.

The darkness gathers in my head. It is black, this day. Blacker than black, heavy and suffocating. And the monster is still at my throat. Its form is that of a serpent, with a thick, muscular tail covered in scales that wraps round and around my neck, pulling tight. At its head there is no mouth or eyes, just a single bird’s talon, a black claw tipped with sharp silver. The claw sinks into the front of my throat and hangs fast.

According to my psychiatrist, the monster is not real. He tells me this apologetically, as if I know it already. Which I do. Of course it is not real. It’s not even a monster, but a somatic manifestation of my illness, a mere, clinical symptom of major depressive disorder. The Throat Monster has a proper psychiatric name, he says, but not a name I’ll like. It is called globus hystericus, a psychological term for “lump in the throat” given to it by Freud. Of course, it must be Freud. Of course, it must manifest most often in women. My psychiatrist’s expression is grave. He knows that I resent that association of hysteria and women.

Why do they call it a “mental” illness? The pain isn’t just in my head; it’s everywhere, but mainly at my throat and in my heart. Perhaps my heart is broken. Is this what this is? My whole chest feels like it’s being crushed. It’s hard to breathe.

I am sitting on the floor, in my bedroom, curled up against the cupboards. I have given up on the bed. I hate the bed and its soft, suffocating embrace. I would like to leave this room, but I can’t. I feel safe in here. Or, as safe as I feel anywhere, which is not very.

How f****** stupid is that? I can’t leave my own bedroom. Me, who used to fly across the world and get on a plane without a moment’s thought. I have been getting on and off aeroplanes on my own since I was 10 years old. I am fiercely independent. I am fierce. Or so people tell me. Used to tell me. I never used to be so afraid. When I was one of his editors, I used to stand up against Rupert Murdoch, arguing with him. I used to be so brave. I used to be somebody.

I am still somebody. Aren’t I? But who?

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