All year I write columns exposing people who threaten ordinary life, but I want now - for once, for a moment - to describe the people who make that ordinary life worth living. For me, near the top slot would be one word: Gran.
This September, a solitary tear symbolised how many of us feel about our grandmothers better than a library of lyrical poetry. In the brutal pressure of the Presidential election, only one thing broke through Barack Obama's superhuman coolness: his granny, Madelyn Dunham. He stopped the campaign to visit her sick bed, and when she died a few days later, at a public rally he let that tear run down his cheek.
Like so many grandmothers, Madelyn had offered Obama the purest love he had ever known. She drudged every day in a bank, setting off on the bus at 7am, so she could send him to the best school in Hawaii. She went without, so he could be all he wanted to be. Obama's mother - like lots of parents, who have kids when they are still nervously trying to realise their own potential - was elsewhere. His father was gone. But his gran was always there, on his side.
A grandparent's love is purer and cleaner and easier than a parent's. You share their genes, but you are not torn from their body. You are an extension of their story, but there is no pressure to be its culmination. You come into their lives when they are in their fifties and sixties, when they are relaxed with the story of their life: they know who they are.
Every Christmas now, I feel an empty ache among the tinsel and the discarded wrapping paper. Louisa May Alcott wrote that "a house needs a grandma in it" - and a Christmas house needs a grandma most of all. But my grandmothers are not here.
My grandmothers came from different worlds - the Scottish tenements and the Swiss mountains. They both left school at the age of 14, and were immediately rammed down the same narrow path: do a menial job, get married, breed, and die. Nobody was interested in their complex dreams and ambitions.
My maternal grandmother, Amy, wanted to take a backpack and travel the world. She was told not to be so foolish and get back to the factory. She did not leave Britain until I took her, in her seventies, to Paris.
My paternal grandmother, Lydia, wanted to be a painter and stared dreamily at Monet, but she was told to get back to the farm and marry a boorish man who proceeded to yell at her for the next sixty years. But she never stopped drawing, and dreaming.
Their generation somehow dealt with thwarted dreams without becoming bitter. Like Madelyn, they spread their hopes outwards, rather than letting them curdle and die inside.
Amy lived with us throughout my childhood, and I never once heard her complain about her life. When she was in her thirties, the husband she adored died suddenly, and she was left with three children to raise alone. Two days after the funeral she began three jobs, starting at six in the morning when she would stumble out into the dark to scrub the public toilets. When I think of her now, she is sitting up all night, reading me story after story. She particularly loved stories about all the distant places she would, she realised, never go to now.
For me, the essence of Amy's life is captured by one night in 2001. My sister had just had a baby and she was broke, so my 80-year old grandmother was on her way to post her £20 she had scrimped from her pension when a speeding driver smashed into her at 80mph. She was thrown over the car and lay on the ground bleeding, her legs smashed and her heart about to stop.
When the ambulance crew arrived, she said to them: "Could you put this letter in the post-box please, because my grand-daughter really needs the money?" Half-dead, her only thought was for somebody else. My sister received the blood-splattered envelope two days later.
As I recount this story, I feel proud of my grandmother, and ashamed of myself. We are - so many of us - betraying our grandmothers. Amy is alive, but she is living in a residential home. She is washed and tended by strangers. She sits surrounded by dementia-addled old people who shriek and groan all day. She is dejected; she does not understand why her life is ending here, like this, after all she has done for other people.
After being run over, my grandmother began to develop dementia. At first, she developed mild hallucinations: she thought there were animals in her room. Gradually, it got worse, and she thought she was being beaten and attacked at nights.
The staff in nursing homes are given no training in how to deal with dementia. None. They would respond to her paranoid fears not by reassuring her, but by laughing awkwardly, making her even more terrified.
Many of them - through no fault of their own - couldn't speak English, and found her accent incomprehensible. One night I turned up and Amy was wheezing and pleading for an inhaler. The staff didn't know the word "inhaler": they had been bringing her glasses of water, bemused. I moved her to another home, paying £1,400 a month, guiltily thinking that I could bribe my way to better care for her. Still it was appalling. They gave Amy grossly inappropriate medication to "calm her down."
For a while she had a catheter fitted, but it began to hurt, so the doctor said she could wear incontinence pads instead. One day I turned up and my gran was screaming. A "carer" had refused to believe her when she said she didn't need a catheter any more, so she was being held down, kicking and howling, while a catheter tube was rammed up her. That was it: I moved her to a third home, where she is - at last - being treated like a human being.
One of the strangest things about dementia is that you have to grieve for a person who is still alive. But even now, when her personality is disintegrating, Amy's fundamental kindness keeps surfacing.
There is one carer she thinks is trying to kill her - but she wanted to get her a Christmas present nonetheless: "She cannae be all bad, and she's got three wee children to look after," she said a few days ago.
My grandmother, at least, knows she is adored, if only in the fleeting moments of clarity when she is still herself. But is this simply the comforting excuse I offer to myself - and my family - for not looking after her ourselves?
And what about all the elderly people left in those first two "homes", and the thousands like them? Most of them had no visitors at all. They would beg for attention, and be pathetically grateful if you stopped to chat for a few minutes. Where were their children and grandchildren?
Yes, a house does need a grandma in it - but instead, we have put grandmas in a home, and discreetly closed the door.