Ihave hesitated to tell this story for more than a year now, as though reporting the details of my father's death could make anything worse than it was. But what happened to him was so dreadful that it won't go away. One Friday evening in the late spring of 1995, he clicked off his television and hauled himself up out of the armchair, ready for bed. The next thing my mother heard from the kitchen was a crash as he fell over, demolishing the occasional table where he kept his boiled sweets, TV listings and remote-control.

He was apologetic about the incident and quite well enough to climb the stairs to bed. A minor stroke was diagnosed by the GP (a similar one had occurred a few years earlier) and admission to hospital for tests scheduled for the following Monday. When I called that weekend, he was quite lucid: nothing to worry about, he said.

Daily phone calls established that my father, aged 76, wasn't getting better in hospital. A scan had revealed bleeding into the brain and the doctors were reluctant to operate on someone of that age. Neither did he seem happy to be there: twice he managed to get out of bed and head for the exits, once getting as far as the car park before collapsing and having to be stretchered back. No one had put up the side-rails that might have kept him in bed.

Within a few days his condition went rapidly downhill. Paralysed down his right side, he lost the ability to speak; his mouth went slack and his eyes unfocussed. We - my mother, sister and I - spent long days and nights at the bedside, holding his hands, talking to him. During that time he was being fed and watered by an intravenous drip; "NIL BY MOUTH" read the card above his head. Sometimes we would spoon-feed him soup, or bring fruit juice in a baby's bottle to relieve the dryness of his mouth. And when you squeezed his hand, he would squeeze it back. There was enough of him there for it still to be my father.

Until three weeks into the crisis, the doctors didn't appear to take an active interest in my father. The consultant would stop by three times a week to say, "Hello, how are we? No change really." There was a change, though. One day I found the drip that was feeding my father had been disconnected. I pointed this out; it was reconnected. Next day, the same thing had happened.

My father's condition was obviously not improving and I wondered if, at a case conference, it had been decided to remove the drip. I wanted to make a fuss, but my mother didn't. "I'm sure they know what they're doing," she said. Mum and Dad always thought the best of men in good suits. Solicitors, accountants, even insurance men always drank their tea out of the best china in our house. From then on, he was only given fluids.

Several weeks later, the doctor called my mother and I into the ward office. Dad wasn't getting any better, he explained; only the fluid drip was keeping him alive and might do so for quite a while. Cases like this, he said, were unlikely to improve; they would usually be transferred to a nursing home, depending on the patient's circumstances. The prospect that was being dangled before us, it seemed, was of Dad lingering on, unrecognisable as the man we loved. The logic was remorseless: wouldn't it make sense to let him go, with all the dignity appropriate to a man who'd served his country, loved his family, and never had an unkind word for anyone in his life? "If we were to take him off fluids it would only take two or three days. He'll go very peacefully."

My mother asked me what I thought, and I squirmed. She herself was in urgent need of surgery on her thyroid, which had been delayed because of my father's ill health. I knew she would go along with the doctor's advice, and, to make her feel better about it, told her that the priority now was to get her well again, and that whatever she decided would be right. So agreement was reached on a solution that made some kind of logical sense, but which, as it turned out, diminished all three of us.The fluid drip was removed.

The process of dehydration is not pleasant to watch. The muscles knot, rock hard under papery skin. Mucus cakes the throat. When I cleaned my father's mouth with a damp swab he would suck at the sponge tip, pathetically. He still managed to cry, though.

It was to take two weeks, not days, for him to die.

Nearer the end, my mother didn't want to come to the hospital any more. She wanted to remember him "the way he was". I went when I could, all hours of the day and night, waiting desperately for him to die. On VE day the nurses organised a party for the old soldiers. My father had been a sergeant in the RAF for about 15 years. After the war he had built up a small business, starting by selling fruit and veg off the back of a lorry around the new housing estates where we lived. He paid his taxes, voted Conservative and believed he would be looked after when the time came. Yet here was all this sentiment about wartime spirit and the sacrifices that people had made, and my dad was lying there, it seemed to me, suffering for want of fluid.

My father's body shrank, and his breathing became more laboured. We were tired and edgy by this stage. One evening I argued with my sister about something trivial and it upset him: he managed to haul himself almost upright, his face contorted in protest. We made it up there and then. The next day was the worst so far: spasms seemed to rack his body despite the paralysis, his jaw was permanently clamped open, his breath a gurgling rasp. All this on an open ward, with the flimsiest of curtains to offer privacy. Couldn't they give him something to make it easier? I asked a nurse. Unfortunately not: his "care programme" couldn't be amended until his next case conference, scheduled for Wednesday. This was Monday.

For a few minutes I just sat there, hoping he would die. Finally, on a nearby ward, I found a doctor who agreed to put him on a morphine drip. After that his body gave up trying to fight and he seemed more peaceful.

On what turned out to be Dad's final morning, my mother was admitted to hospital too, for urgent tests. I alternated with my sister: she stayed with one parent while I visited the other. Thus it was that at about midday, when he died, my sister was with him. My mother came out of hospital long enough to arrange the funeral, summoning enough strength and composure to preside over a family gathering in our garden afterwards, returning later for the surgery she had postponed for so long. Three weeks later, however, she died of an undetected aneurysm, a rupture of the main aortic artery..

We hadn't expected the hospital to perform miracles; what we had hoped for was that my father would be made comfortable. Perhaps the doctors thought that withdrawing fluids was for the best, but it did not give him the quick, peaceful ending they had told us to expect.

Certain actions and incidents set people apart from others,leave an indelible mark on the consciousness. I will never be able to forget the way my father died. It will take a long time for the guilt and grief to go away.