Anne Karpf: There's no such thing as a perfect mother – and that's half the fun

Raising a family is less stressful when we don't try too hard, says a mother-of-two. The Campaign for Real Mothers starts here...

There's been a lot of whispering over the past week in my house, along with a few shouted "Don't come in"s. While I've feigned ignorance (pretending not to notice is an important maternal skill), of course I've known full well what's been going on: something to do with Mother's Day. And even if the outcome is just a piece of burnt toast and a cheesy card, I'll feel touched and loved.

But I'll be feeling something else too: undeserving. This is a) because I have to work today and so will have to ignore my children's every need, but also b) because almost every single thing I do for my kids, my husband does too (though he does draw the line at entering the portals of Primark and Topshop).

What shocks me about this confession is that it demonstrates how, despite three decades of feminist debate, some of the stereotypes of motherhood – a person whose attention is focused exclusively on her children, a woman who does things that no man can – still persist so strongly and have been internalised by all of us, most especially mothers themselves.

Images of the idealised mother have become in some respects more entrenched and powerful over the past decade rather than less. Think of the celebrity mother – the Angelina Jolies, the Madonnas – those women who, it seems, can't have enough of children (or enough children). Think of the resilience of the myth of maternal-infant bonding – an instant love-affair – even though it is based on the shoddiest, widely discredited research.

Accompanying idealisation, as any psychoanalyst will tell you, there is always denigration: if you believe in the existence of the Good Mother, it stands to reason that you'll also subscribe to the idea of the Bad one.

And my, how the tabloids like to point their moralistic finger. Britney Spears driving with her baby on her lap – Bad Mother! Julie Burchill leaving her kids and their father for another man – Very Bad Mother! The choice is stark: you can be very very good or you can be horrid. And sometimes, in the case of Kate McCann for example, you can move pretty swiftly from Good to Bad.

It's not surprising that there's so much postnatal depression about. Not only are squads of hormones swirling around your body and you're required to assume responsibility for another human life immediately after the physical endurance test known accurately as labour, but you also know that you'll be judged by politicians, by educationalists – jeez, even by complete strangers – on how well you perform this new role. In fact it's surprising that the Government hasn't yet introduced, alongside Ofsted and Ofcom, Ofmum: that way they could rank us, set targets, and openly name and shame.

And yet shockingly, there is still a taboo against expressing the sort of emotions articulated by the poet Adrienne Rich when she wrote: "My children cause me the most exquisite suffering of which I have experience. It is the suffering of ambivalence, the murdering alternation between bitter resentment and raw-edged nerves and blissful gratification."

The psychoanalyst Donald Winnicott put it even more bluntly when he said that mothers hate their babies before their babies hate them. We hate them, he suggested, for 18 reasons, among them the fact that the baby interferes with her time for herself, and treats her like an unpaid servant (go, Donald!). But I like the novelist Fay Weldon's formulation best. "The greatest advantage of not having children," she once said, "must be that you can go on believing you are a good person. Once you have children, you realise how wars start."

That we have to keep relearning this is plain to anyone who listened to last week's Woman's Hour. There, caller after caller confessed to feeling ashamed because they didn't enjoy every second with their child, or sometimes resented them. These mothers – some of whom had been nursing feelings of self-reproach for decades – were judging themselves by the highest, unachievable standards, and then, inevitably, failing.

The reality of mothering is less uplifting. Motherhood for most women is literally impoverishing. Figures released last week show that, once they have children, even highly qualified women take less-skilled jobs in order to spend time with their children. This isn't necessarily a bad thing, were it not for the fact that fathers aren't similarly affected.

The rise in property prices has had a major impact on mothering: few households can survive on a single income today. This means that what mothers who work outside the home have least of is the resource they most need to do the job well: time with their kids. Don't talk to me about flexitime. For many women it isn't a reality – you can request it but your employer isn't required to agree to your request. Nor is it financially feasible. Many others, like night cleaners, have brought it into their lives themselves, though it often brings with it flexisleep (aka not enough).

And at a time when women's contribution to the household economy is essential, the tasks involved in mothering have grown exponentially. My mother wasn't required to do half as many things for her kids as I must do to mine if I'm to avoid censure. I'm supposed to help my children with their homework; when I was a kid there was a line painted at the entrance to the school that parents weren't allowed to cross. I was allowed to play out unsupervised, but mothers today must chauffeur their kids everywhere – no wonder there's global warming – or risk them turning into couch potatoes.

The truth is that, although we idealise mothers, we don't actually value the things they do. The title of Naomi Stadlen's brilliant book says it all: What Mothers Do – Especially When It Looks Like Nothing. Stadlen noticed that mothers who have spent all day looking after babies and interacting with them, when asked what they've done all day, often say nothing, and feel that they should have done more with their time.

In fact it's time spent with children doing unremarkable things – fooling about, concentrating on something together, even watching a television programme together – that is often the most satisfying. I do best, it turns out, when I do least.

Objectively speaking, my kids are the most beautiful, brilliant, funny, loving and lovable children in the entire world. But I'm a much less good mother than I thought I would be – far more inconsistent (violating the First Law of Mothering), volatile (I can go from nought to nuclear in five seconds), and sulky ("do it yourself" has increasingly become my mantra). I'm trying to train my kids to have low expectations, and to get used to benign neglect.

But I've also taken the advice of Rozsika Parker, the author of Torn in Two: The Experience of Maternal Ambivalence. When mothers acknowledge their mixed feelings towards their children, she says, the see-saw of love and hate that they invariably feel, then they deepen their capacity to mother.

We also need collectively to let go of our fantasy of the perfect mother. None of us has had one: part of growing up is coming to terms with the real mother we've had rather than the perfect mother we wish we'd had. A mature society is one that doesn't ask the impossible of mothers, or indeed fathers.

For myself, I'm working less hard at being the good mother these days, and accepting my shortcomings. My children, it must be said, are playing their part in this project by helpfully pointing out all the ways in which I fall short. We've had a Campaign for Real Ale. Perhaps it's time for a Campaign for Real Mothers. Happy Real Mother's Day.

Can the modern mother ever live up to the misty image projected in art, books and film – or is the reality actually much more impressive?

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