I have more fingers on one hand than I have facts about my father. Let me rhyme them off: his name was John, although, because his family were Highlanders, they called him Iain.

He went to Hyndland Secondary School in Glasgow. As a student he worked in the ticket office in Queen Street station.

And he was an alcoholic. That last is a fact I've never said publicly before.

In the past couple of weeks I've been interviewing people living with alcohol addiction and every one of them spoke of shame and how it stopped them seeking help.

Shame is terrible, one woman told me. It keeps you silent.

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One man I interviewed, David, told me that after 40 years of drinking he is now in recovery. A miraculous thing had happened. He had last seen his daughter 20 years before, when she was five, and he had found her on Facebook. They were talking again.

He was prioritising her needs, taking things slowly, but desperate to build a relationship with her again. Imagine that. Your daughter is out there, unknown, and then here, on your computer screen, within reach.

To my embarrassment, because it is self-indulgent and deeply unprofessional, I started to cry. For the bulk of my childhood this is what I had wanted - for my father to reappear. Preferably full of contrition and having remarried and created me some half-sisters. But I would have taken what I was given.

All I knew was that I had no father. I didn't know why and so I internalised it. She must have been a pretty awful kid, if her own father wasn't interested. I worked diligently at school and my extracurricular activities to try to be the sort of girl whose father would want to be around.

I knew my parents had been married but the man was never, ever mentioned. My mother, like Mary, who I learned about at church (of course, I went on to be a Sunday School teacher) had all but produced me single-handedly.

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I had no anger over being abandoned, just hope of a sunlit return.

You don't really think about how much you have when you're a child, and I had plenty. You focus on what your peers have, and you want that too. A dad is trickier than the newest My Little Pony. You can't get one with pocket money. Instead, I filled in the gaps, invented a new life and a cover story for him.

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Ageing is to be increasingly haunted. I have a much beloved but estranged aunt and I see her face now when I look in the mirror, which is a particularly eerie form of possession. An opaque ghost father followed me for many years and then, when I was in my late teens, he died. So that was that.

I'd been so spurred by hope until his death. There was, however, still no mention of what killed him. As an adult, living in Australia, where he lived in his last years, I went to the Births, Deaths and Marriage register to get his death certificate, thinking it may be of some use.

Next to "Children", it said "unknown", which felt personal but also frustrating as I'd wasted a beautiful Sydney afternoon in an administrative office in Pyrmont when I could have been at the beach.

Though there was some use to it: it told me that he had died of liver cirrhosis and suddenly the silence made sense. The shame of addiction can be pervasive not only for the addicted person but also the family.

My mother had always placed great store in being of good character and I felt I could never mention his alcoholism because it would damage my good character.

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I was angry about it. Furious. I had missed out on having a father because he chose to drink instead? What an abdication of responsibility. What an insult. I stopped caring, the little bit that I had.

My dear friend also had an alcoholic father and tells dreadful stories of the humiliation wrought by his behaviour, and the strain on his mother keeping the family ticking on.

It was, I decided, a blessing that he had absented himself. I began to understand how difficult this all must have been for my mother and understood the situation to be her story and really very little to do with me.

I have said exactly this before but it bears repeating: I know lots of fatherless children and we all have our stories. The fathers become ciphers in these tales, they become who we need them to be in order to explain away our foibles and bad habits.

We have lost them to alcohol and suicide and illness and accident, sometimes just plain fecklessness or even disinterest. And we think it makes us interesting but in fact it doesn't, it makes us common.

There is probably some useful examination to be done on the effect of fatherlessness. I would say none, for me, no effect. But that is more likely arrogance and an unattractive resistance to self-examination.

I think I deal poorly with rejection as a result. I form very strong attachments - if you are my friend then I would drag bodies across floors for you, no questions.

It has given me the sense that men are entirely superfluous, which is probably a little unfair, and given me an absolute and pure love for my male friends, who are helping correct that unfairness.

Most of my male friends have been involved in the production of boys but the odd two or three have small daughters and I love them all the more for their openness and dedication to the task of raising girls.

Being envious of toddlers for their devoted dads is quite an unedifying space to occupy, let me tell you, but it's coupled with love.

When I read the MSP Monica Lennon's letter to her father, who was also addicted to alcohol and who died, I thought about what I might say to my own. Nothing, I don't think.

But I have still felt too ashamed of his addiction to talk about it. Which is ludicrous because I have so much compassion for other people who are similarly afflicted and an understanding of the harm of shame.

Men like my father, in the west of Scotland, and elsewhere, die of silence. Yet alcoholism is nothing more or less than a fact.

Actually, I have now some more facts. On Sunday I finally asked my mum about him and I learned that he liked to read; he always had a book in his back pocket and was fond of the Beat Poets. I love to read too.

"You get that from him," my mum said. It was the first time I'd ever really thought of him as a person. And that's something to be ashamed of, that fact.