Struggling to pay at the supermarket till, I felt that childhood shame flooding back

Our bank card has been declined at the supermarket. It’s no big deal – a glitch. But I’m experiencing flight-or-fight responses: heat rising up my neck, my heart thundering. I can’t meet the cashier’s eye.

The rational part of my brain understands that this is idiotic. I recognise that knowing we definitely have money in the account is an entitlement in itself. But the irrational part is shuttled back to the many, many times in my childhood and teens when there was never enough cash. Back to carefully counted stacks of two- and five-pence pieces, often hunted out of the back of the sofa or rattled from mostly empty piggy banks.

My middle-class husband smiles, shrugs, apologises to the people waiting behind us and taps the card again. Perhaps “middle-class” and “comfortable” are often used interchangeably because, among other things, they mean you will never feel the extreme discomfort of reliving the echoes of poverty well into your 40s. When we leave, I am almost in tears. “What must they think of us? And we were buying baby food!” My husband is kind, but bewildered. As well he might be.

Often, this scarcity mindset will knock me right back to my time in the 80s living on council estates, where the corner shops had metal grilles in front of the booze, fags and cash, and a sign saying “Do not ask for credit”. I grew up knowing that, although everyone where we lived was poor, admitting it was worse than enduring it. And I still feel this way.

There were times in my 30s when I was an award-winning author writing about poverty, yet almost homeless, down to my last tenner, and not a soul, not even my closest friends, knew. Instead, I did whatever work I could find – memorably, coercing pensioners to answer fitness surveys in a call centre in West Ruislip that always smelled of Chicken Cottage boxes – and skipped meals until my paycheck came in.

If you grow up poor, it takes a long time to shake off the shame, the secrecy of it – if indeed you ever do. Even when you are not poor, there are mental gymnastics involved in freeing yourself from the scarcity mindset. I am not extravagant. I feel guilty enough about having the luck to live a better life without wearing a Gucci hair shirt, too. I still buy almost everything secondhand. But I have stopped getting the absolute cheapest, and Terry Pratchett was dead on with the boots theory and I wish I had spent more than £25 on my ill-fitting wedding dress that I had to tape to my boobs. But old habits die hard. If I buy so much as a new saucepan – something I want, but don’t need – I will revisit my elaborate budget and redo every sum to account for the £15.

Related: I can’t afford to heat a pizza for my son – this is the reality of Britain’s cost of living crisis | Jo Barker-Marsh

There are positives, too. I am grateful for everything I have and rarely envy anyone else’s lot. I know if I ever find myself on that poverty cliff edge again – and that could be any time for most of us these days – I will manage. I remind myself I spent a decade trying to ensure my kid wouldn’t grow up as I did – and he won’t. He will never be aware of every penny, every privation, from the time he is old enough to add and subtract. I still buy him mostly secondhand stuff, but I take joy in getting him what he needs and, just sometimes, what I want to give him, for no other reason than that he, like all children, deserves some good things.

Some cuts I won’t make. I have travelled, because my peripatetic childhood taught me that there was always a new start to be had. If I can, I will always have extra food. The heating goes on in October. These things matter to me. They make me feel safe. A warm house and full fridge are what I want my kid to have, so that when he is grown and his bank card is refused, he won’t be hurtled back 30 years, but will smile, shrug and apologise.

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