There’s a mum at my daughter’s primary school who went to the very same school when she was a little girl. She swaggers across the playground as if she owns it, and  acts as though she’s the arbiter of everything and anyone who is right and proper at the school.

In the beginning, I was beguiled: she acted as a confidante, looked after my daughter after school, on occasion, invited me round for hot chocolate at her house, and shared her own little marriage challenges. It took me a while to realise that she used this ‘I’m concerned about you’ pretence for her own purposes – as I learned to my cost.

She has turned out to be hugely competitive, in a bare and raw way (which she is totally unconscious of), but cloaked the pill of her resentment in the disguise of an evil pantomime stepmother. I prefer aggression to be aired in a clean, obvious way; then I can confront it, ask help with it, or just plain avoid it (depending on my mood and the severity of the issue). With this particular woman, I’m convinced that her sweetness of tone and self-righteous demeanour masks an inner bitterness and emptiness that acts out in a sweetly spiteful way.

If she were a perfume, she’d be the kind of scent that promised a lot from the sidewalk but which turns rank and itchy after 20 minutes on the delicate skin of your inner wrist.

This so-called friend gloated today about  my daughter, L, being ‘out’ in an after-class fun disco activity – saying that L was in tears for inappropriate reasons. This comes a few days after my daughter is triumphant in a dance competition, and who was asked by the head to show off her medals in an assembly for achievers. This woman’s son isn’t one of the gifted and talented of the class. I’m wondering if there’s any coincidence here: in her attempts to thwart L from winning yet another trophy, and by implication me, this woman’s sourness emanated instead from her holier-than-thou insistence that L was out. “Sorry,” she said to me, eyebrows and lips smirking; clearly not sorry at all.

I laughed it off, but resolved to volunteer to be one of the adjudicators at the next school disco. In the meantime, I’ve been casting around for advice on the web, and there’s a bunch of stuff advising on competitive mothers. Think I’ll go with the advice of Dr Robi Ludwig: “If you can’t turn that overly competitive friend around, it’s OK to sometimes say, “This relationship is just not for me!”