The second time I visited Dad over Christmas was far less rosy than the first. It was Boxing Day but decorations at the home had already begun to wilt. And this time, instead of finding Dad sitting in the main room cleanly shaven, my husband and I are told he is still in his bedroom.

I walk down the corridor with trepidation. His bedroom scares me. While many of the residents have cosy rooms, personalised by their families with photographs, lamps and cushions, Dad’s is a barren, institutional space.

It’s not that we haven’t tried. When he first moved in, my mum and sisters took pictures and got a television mounted on the wall. But none of it lasted long. Dad’s habit of destroying things in the night meant that nothing was safe. Now there’s just an empty bracket where the TV was, and the walls are blank, save for pockmarks and the odd, unidentifiable smear.

The focus of the room is his bed, a hospital one with bars to stop him slipping out. And today he’s lying in it, his head tilted to the window and his bare torso only just covered by a sheet.

“Dad!” I say, leaning in to kiss his cheek. He looks at me with blank incomprehension and turns back to the window, plucking at the sheet.

He doesn’t look comfortable, his body is twisted like a broken toy, and I’m shocked at how thin he is. It’s 11am, but he seems sleepy, unable to focus.

“Perhaps it’s the medication?” I say to my husband, who is behind me, hands in pockets, face set to neutral. I know Dad’s been given morphine patches since his recent deterioration, but they didn’t seem to be making him so woozy last time I was here.

“What’s that out there?” says Dad, pointing at the window, which opens on to the residents’ “garden”, a concrete courtyard with benches. “I’m not sure,” I say, following his gaze to a pebbledash wall. There is nothing to see.

One of his carers bustles in. She’s a smiley girl who greets Dad with a thick Cornish, “All right, Peter?” to which he responds, automatically, “All right.”

She turns to me, eyes kind. “We hadn’t got him ready for the day yet, so we’ll just do that …” Another woman enters and they start fixing his bed.

As they move the sheets, there’s a smell and I realise his bedding is soaked. “We’re going to have to change these sheets,” she says to her colleague.

“I think we’ll wait outside,” I say, rushing my husband out to the hall. How I wish, guiltily, that I had arrived half an hour later, to be presented with the freshly laundered version of reality.

Once they are done, Dad is a bit brighter. Another carer brings in his breakfast – a marmalade sandwich and a plastic beaker of milky tea. “I’ll feed it to him,” I say and she offers me some disposable gloves on her way out.

The sandwich breaks down easily in my sheathed fingers and I tear it into manageable mouthfuls. At least Dad is eating solid food again, even if it doesn’t really involve chewing. He’s acquiescent, but it’s a slow process and he struggles to lift his head.

It’s clearer this time how immobile he is since his most recent episode. I don’t think he can walk properly or bear his own weight. And the horror of being trapped in this room, trapped in his head, strikes me afresh.

How much more suffering can one person take? That’s what I can’t comprehend. Yet I know, from others who have relatives in the same plight, that things can get even worse.

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http://www.guardian.co.uk/lifeandstyle/2013/jan/19/dads-dementia-worsens-after-stroke