Imagine your house is on fire, and when you dial 999 the call handler suggests you try putting the blaze out yourself. Resources are tight, you see, and demand high, and the service increasingly relies on volunteers. Or perhaps your child’s maths teacher is off sick. The headteacher texts and asks if you can leave work to explain algebra to the class. It’s your family, after all, so shouldn’t you be the one to help?

The idea is ludicrous of course. And yet that’s exactly what is happening to the almost 6 million people in the UK who are unpaid carers for sick, disabled and older relatives. While we rightly wince at headlines of DIY dentistry and patients on NHS waiting lists crowdfunding for surgery, it has long been normalised for family to fill the gaping holes in the social care system.

That’s only increasing. As need has grown and reform and resources have stalled, 1.9 million people in England alone provided a “full-time” (defined as 35 hours or more) week of care in 2023-24 – that’s 70% more than 20 years ago. Others have to fit caring responsibilities around their jobs: dropping off the kids at school, going to the office and then helping their elderly parents bathe and eat.

Let’s call them the nation’s ghost workforce: a growing army of unpaid cooks, nurses, cleaners and physios who slog away day and night, out of sight behind their front doors.

Nessa will be 60 this year, but, as one of the UK’s ghost workforce, instead of planning her retirement, she’s worrying who will care for her son. Jai, 36, has autism and multiple physical disabilities that mean he’s largely bedbound and lives in daily pain. Since Jai’s care package was pulled by his local authority in 2017 after a “budgetary review”, Nessa has been her son’s sole carer.

I spoke to Nessa over the Easter bank holiday weekend. While many of us enjoyed time off, she was doing her usual 24/7 shift: helping Jai move around, administering medicines and changing dressings on his bleeding ulcers. “I’ve not had a break in nearly 30 years,” she says.

Nessa is disabled herself – she has osteoporosis as well as severe muscle and ligament damage – and the physical toll of her caring role means she struggles to walk more than a few steps or leave the house without help. Often Nessa gets to bed at 3am. Sometimes she doesn’t get a chance to eat for days. “Extraordinary things are demanded of you, and all you can do is rise to the challenge,” she says. “That’s what carers do.”

What does the government give Nessa for her extraordinary work? £86.45 a week in carer’s allowance. Added all up, Nessa calculates that she cares for Jai 133 hours every week. That’s the equivalent of being paid 65p an hour.

And yet the main rate has only chugged along in 50 years, slowly increasing with inflation by a few quid here and there but never coming close to matching the cost of living or rising wages. If carer’s allowance had kept pace with the growth in earnings over the years, today’s carers would receive an extra £160.46 a month on average, according to new research by Carers UK.

The result of this shortfall is damning: 62% of those receiving carer’s allowance live in poverty.

In fact, the vast majority of carers don’t even receive carer’s allowance due to extremely tight eligibility rules. For example, child carers – itself a term that legitimises the indefensible – aren’t awarded the benefit until they are 16. Many adults are denied it because they don’t do “enough” hours of care to qualify, they earn more at work than the income threshold or the person they care for doesn’t get the right qualifying social security. It’s no wonder the official term for family carers is “unpaid”.

Meanwhile the government saves a fortune from the free labour: family carers provide support valued at more than £184bn a year in the UK – up by nearly a third since 2011. That’s more than three-quarters of the entire expenditure for the NHS.

This is not simply a matter of money but of the scale of work demanded of carers and the conditions in which they are expected to do it. Human beings naturally look after our families, often asking for little thanks in return. As Nessa puts it to me: “I care for someone I love, so it’s a sacrifice I’m prepared to make.”

But the fact that many people will sacrifice their health and income for loved ones does not mean a modern state should ask them to. Or that disabled or older people being cared for should be denied a choice in who provides their support.

Successive governments’ reliance on unpaid carers is in many ways an exploitation of love in which one of the most innate impulses – to care for family during their old age or ill health – is used to save the state money with little regard for the human cost.

The recent carer’s allowance scandal – which saw thousands of carers falsely accused of fraud – sums up, at its extreme, the neglect or outright disdain the state shows those it should be supporting. As the government-commissioned review into adult social care ploughs on, and the population grows older and sicker, it is surely time to finally reflect on the role of family carers. How much can society expect of the individual and how much of the state? What financial support do we owe the millions of people propping up the care system? And why is it still taboo to say they should get it?

As we finish talking, Nessa admits she has another worry. Since her health has worsened, she’s had a care worker herself for six hours a week to get to the shops and clean the house. But her council charges her a £200 a week “contribution” for it, and she’s scared that rising food and energy bills mean she’ll lose that one scrap of help soon.

“Carers are the hardest-working people you will ever meet,” Nessa says. “Who cares for the carers?”

It is a question the country is long overdue asking.

• Frances Ryan is a Guardian columnist and the author of Who Wants Normal? Life Lessons from Disabled Women