The dilemma From very young, my daughter had a best friend whose mother encouraged the relationship, referring to them as sisters and insisting on them attending the same clubs. This friend became obsessed with my daughter and didn’t allow her to make other friends. The child’s work always contained characters with my daughter’s name and she would write how angry she was when my daughter wouldn’t do what she wanted.

After five years my daughter was being emotionally and physically abused – threatened, held down, followed. She would raise my daughter’s skirt to embarrass her and touch her. My daughter couldn’t eat or sleep and put a note under my pillow that broke my heart, saying she couldn’t carry on. The school immediately called the parents in.

Since then, the friend’s mother has never spoken to me, except to show she despises me. Our paths cross in our small community, but I’ve never had the chance to explain how desperate and ill my daughter had become. I’ve offered to talk it through, but it wasn’t welcomed. My daughter has taken a long time to recover her confidence. I want us to move on, but the disrespect means I can’t. Should I accept the bile or tell her a few home truths?

Mariella replies Neither, I’d suggest. Your daughter sounds like she is moving on from her trauma, but your letter suggests she’s doing better than you on that score. This woman’s disrespect seems a small price to pay for the end of your child’s ordeal. She’s unlikely to thank you for identifying her kid as the demon in your daughter’s nightmare. We’re bad enough at accepting our own failings, let alone those of our children.

She’s not doing anything worthy of your continuing sense of grievance, apart from failing to admit culpability or seek reconciliation. “Disliking” you and giving you a “wide berth” are both pretty understandable under the circumstances. She’s hardly going to thank you for opening her eyes about her daughter. I’ve yet to meet any parent who embraced news of their child’s bullying or other dysfunctional behaviour with understanding and empathy. More often than not they’re in a state of denial and ignorance equal to that of their troublesome offspring. If that wasn’t the case, bullying would be so much simpler to resolve. You’d just sit down calmly with the parents, explain what their kid was getting up to and off home they’d go to sort the situation out.

The sooner you forgive this girl, the better you will start to feel

It’s pretty hard to hear home truths about the children we raise, not least because their outward behaviour is a reflection of what they’re feeling inside. It’s not always a parent’s fault when their children become unmanageable – there are many external factors that can contribute – but it is our duty as adults to be alert to the signals. No child is born bad; they glean their behaviour and communication skills from the environment around them. Show me a bullying, angry, controlling child and I’ll immediately start looking for the responsible adults steering that life. As Philip Larkin famously said: “They fuck you up, your mum and dad,” and seeing our handiwork in sharp relief is rarely a pleasant prospect.

That doesn’t mean we can work miracles, cure kids of their illnesses (mental or physical) or join them in jail if they become criminals. It does, however, mean that the increasingly dysfunctional behaviour of your daughter’s one-time friend is not a mere character flaw but down to some kind of emotionally traumatising influence that has set her on her troubled path. Her need to control, her precocious sexualised behaviour, her anger and her desire to humiliate would all be sounding loud warning signals to me. You’re not the one to tell her parents that, but I’d hope that the school is keeping a close eye. I’m surprised that this girl wasn’t recommended for counselling, or her parents advised to engage with social services about her antisocial behaviour. (Help can be found from Family Lives on 0808 800 2222).

I understand your frustration and the desire to close this sad chapter conclusively, with recognition of what you’ve endured, but pursuing either is likely to cause you further distress. The most healing thing you can do is accept that this girl, no matter how painful her impact on your daughter, is not responsible for her actions. She’s the innocent victim of circumstances outside her control. The sooner you forgive her, the better you will feel. Allowing your anger to continue unabated is not good for any of you. I am sympathetic to the wounds you still bear but am certain it’s an encounter you need to come to terms with, not seek recompense from.

Unless help has been forthcoming, this child remains trapped in that troubled place while yours can move on with her life and hopefully pursue happier friendships. Much as it might feel briefly empowering to share your “home truths”, my bet is that this girl’s family are more than aware of whatever you have to tell them. Sympathy for whatever is causing the girl’s trauma is actually your most powerful weapon.

If you have a dilemma, send a brief email to mariella.frostrup@observer.co.uk. Follow her on Twitter @mariellaf1

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