The first time I meet Julie Bailey, back in June, she is in Breaks, the cafe she has run for five years just off the high street in Stafford. The cafe is closed, and Bailey is packing up and moving out. This is no simple relocation. In the time Bailey has been here the cafe has doubled as the headquarters of her campaigning group, Cure the NHS, which initially worked to expose the lethal failings of the local Mid Staffordshire NHS foundation trust, and which latterly has extended its reach to hospitals across the country. Cabinet ministers have sat at these tables to hear Bailey's emotive story; for a while the former chief executive of Mid Staffs, Antony Sumara, would come here to face the grievances of some of those his hospitals had let down before he took over in 2009. Now all of the remaining tables and chairs are piled high with boxes of letters and case notes, testament to the five years that Bailey and her supporters have put into their campaign for justice and accountability.

There was a sense, when the report of the public inquiry into Mid Staffs conducted by Robert Francis QC was published on 6 February this year, that Julie Bailey's indefatigable work might be done. The Francis report damned the absence of "care, compassion, humanity and leadership" at "all levels" of the trust. Almost every sentence of its judgment was a vindication of Bailey's outrage, which had begun with what she saw as the gross negligence and cruelty in the treatment of her 86-year-old mother, Bella, at the Stafford hospital in the eight weeks before she died in 2007. Bailey was interviewed on television outside the houses of parliament to welcome Francis's findings, which confirmed and extended those of the Healthcare Commission report of four years earlier, and to call, unsuccessfully, for the resignation of Sir David Nicholson, chief executive of the NHS.

Having been instrumental in bringing into the open the full extent of the scandal of a hospital trust that was seen systematically to have put the meeting of performance targets ahead of the most basic patient care, Bailey might have hoped to have been greeted as a local hero in her home town. In fact, when I meet her four months on from that February afternoon, she wears the look of a woman whose struggles are only beginning. Having long since used up all of her money on her campaign, sold her house to finance her frequent necessary trips to London (which included attending every day but one of the inquiry), she is moving to live in a caravan 50 miles away from Stafford, in the knowledge that she has effectively been run out of town.

You don't have to talk to Bailey for long to realise that she does not give in easily. The decision to leave the cafe and to leave Stafford feels like a defeat for her, and not one she bears lightly. "We had our first meeting here in January 2008," she says. "I put the ad in the paper for people to come forward. Twenty five or 30 people turned up that first time, and 15 of them are still with us. The others who came were what I call lone wolves. They could not get beyond their own grief or grievances. I don't blame them for that. It does affect some people really badly. But the ones who stayed have been through a lot with me; we have become very close."

A couple of those stalwarts, Jim Duff and Castell Davis, who also saw loved ones betrayed by the lack of care at Stafford, are busying themselves making tea and packing boxes. In the hours that I talk to Bailey, several others put their head around the door to wish her well before she goes. I wonder why she feels she has no choice but to leave?

"It became clear I would have to go in December 2012," she says, "when they decided to close A&E overnight for patient safety reasons. What I didn't know was that our opponents were saying that had always been our agenda." One blog post, widely read in the town, suggested that Bailey had stood up at a public meeting to say she wanted the hospital closed and all of its staff sacked. Bailey has evidence from the chair of the meeting to prove that was not the case. "I only said what I said the day the Healthcare Commission report came out in 2009: that we needed to go through the hospital ward by ward and shut each one down in turn and not open it until it was transformed. One of the difficulties we found is that there is no such system in the NHS to go into a failing hospital in that way. They are just left with bits of sticking plaster."

Right from the start of the campaign in 2008 Bailey was getting anonymous hate mail, which she took to the police. The hospital is Stafford's biggest employer, and her exposure of its culture of neglect and harm was profoundly unpopular in some quarters. After the emergency department was closed at night pending review, she says, the abuse got worse. "I was getting cards saying 'I hope you die in an ambulance on the way to hospital now you have closed this one… ' I had my car tyres slashed, 'Bitch' written on my windows, and 'Shut your effing mouth'."

Bailey, a mother of two who lives alone, was understandably worried for her safety. She finally decided to move out when her mother's grave was vandalised. "I would go up each Sunday to put fresh flowers out, and when I went up on a Tuesday to water them the flowers would be out and the vase smashed and the pieces stamped into the earth so I would have to dig them out," she says. She thought it might just be kids, but then she got another thank you card, this one asking: 'Isn't it about time you started looking after your mum's grave? Ha ha ha…' I don't really know how you deal with that," she says.

Though she does not know who sent those threats, Bailey is in no doubt she has made powerful enemies in the town, which has divided partly along political lines. "We had exposed the council at the public inquiry," she says. "I had written to its scrutiny committee asking for help and in return they sent me a solicitor's letter warning me to back off. And we helped to get rid of the MP, David Kidney, who was Labour. We actively campaigned against him, because he did nothing whatsoever to help us, while David Cameron had promised us a public inquiry if he was elected. It seems the local Labour party have not forgiven us for that."

As the weeks and months went on with not a single hospital staff member disciplined or dismissed as a result of the reports' findings it became easier for Bailey's vocal opponents to claim the more extreme facts – of patients left to drink from flower vases – were lurid media myths. Two Stafford nurses have recently been removed for falsifying A&E records, but most other complaints have been dismissed. "We still have a situation here that a proportion of the population don't believe anything happened," she says. "The local Labour party are saying that; the hospital staff are saying that." The veracity of the widely reported figure of "400 to 1,200 excess deaths" in emergency care between 2005 and 2008 at Stafford has become a subject of angry debate among amateur online statisticians. Whatever the number, not one death has been proven to have been caused by negligence. "There was a case-note review," Bailey says, "which Alan Johnson [then Labour health secretary] brought in. It was supposed to be independent, but I no longer believe anything is really independent in the NHS. Ninety people applied. But the case notes were obviously supplied by the hospital and at best incomplete. On the day Mum died there was nothing in her notes at all, for example."

Does she ever feel she has gone back to square one? "No," she says, firmly. "I feel full of optimism that we have opened that door and people now feel a bit safer in speaking out. We don't want to destroy the NHS, far from it. Six, seven years ago I was so proud of the NHS, Mum too. We'd always had fantastic care. What other country did what we did? But I do think we have lost our way. I believe the government has to be honest and say we just can't afford what we are trying to do. We put on bionic arms and all sorts. Miraculous things. But we also have people lying in beds with terrible pressure sores and dying of dehydration."

Because Bailey's cause has been adopted in particular by the Daily Mail, and because her campaign plays into the hands of those on the right who may have a privatisation agenda, Bailey has come to be seen by some – not least in Stafford – as a stooge for the Tories. She roundly rejects the charge. "I am no fan of privatisation," she says. "Never have been, but I am at a point where I feel, after seeing what I have seen, I would go for any kind of system that is safe."

A former social worker specialising in care of the elderly, and a lifelong Labour party supporter until seeing the defensive spin of the Brown government at first hand, Bailey feels let down in particular by the way the professional bodies and unions closed ranks after the reports. "The director of nursing got off and continues to practise," she says. "I decided only to complain about one nurse on Mum's ward, and I got a note back from the Nursing and Midwifery Council [NMC] saying I had identified the wrong nurse. The hospital had supplied a duty roster to say she was not on duty the night I said she was. You can't challenge those judgments. That's the end of it. I hear she has been promoted."

Bailey demanding the resignation of Sir David Nicholson, the NHS chief executive in February last year. Photograph: Martin Rickett/PA

As a result of her visible campaign Bailey has become a lightning rod for the whole country's complaints about the NHS. They are, literally, piled up around her. "You get to know where the big problems are quite quickly," she says. "Particular hospitals, particular wards. We knew all about Morecambe Bay. Basildon is a bad one… " She feels duty bound to reply to them all.

"Every case is terrible in its own way," she says. "I tell people they have to go through the complaints procedure, though it's a torture, and nothing will come of it. At least now we have Ann Clwyd [the MP who is advising the prime minister on NHS complaints, and who was critical of the hospital care received by her own husband before his death] doing something. I can direct them to her."

Despite her hard-won intimacy with the Kafkaesque internal machinery of the NHS, its corporate board structures and overpaid quangos, the Quality Care Commission and the rest, Bailey has been wary of being co-opted into any reform process. "The prime minister invited us for tea, but when we said we wouldn't meet [NHS chief} David Nicholson, tea was off." When the group did visit No 10, Jim Duff asked the PM if he knew that directors at the Mid Staffs trust had been earning double his salary. "Cameron did not know how to answer," Bailey recalls, "Eventually he said 'complex things to run, hospitals'. 'Not as complex as the bloody country', Jim said."

I'm guessing that Bailey's mother would have been proud to see her daughter arguing her case. Is her sense of injustice inherited?

"It is," Bailey says. "Mum always had a campaign. Her last one was about local paper boys being made to carry too many papers. She'd had a stroke by then, but she got stuck into it. She wanted those boys to have a trolley, but in the end she just got them a bit more money."

Even though she has gone over the stories a hundred times, had the cathartic experience of including them in her self-published book, Bailey's voice still breaks when she talks of her mother. Her will to fight is explained partly by Bella's biography.

"As a girl, Mum's family ran a cafe in Park Lane," she says. "In the war she joined the WAAF [Women's Auxiliary Air Force] but ran off and as punishment the authorities sent her to work in a munitions factory, which is how she ended up in this part of the world. One fateful night she met my dad on the way home from a dance. That was really when her life ended, in a way. She ended up having six children with him and he was a real bastard to her, left her when I was a baby. She just worked and worked to keep a roof over our heads. And she was so kind. Christmas Day we would have homeless people in around our table. She hated injustice."

Has Bailey ever met the nurse she thinks most responsible for her mother's ill-treatment since Bella's death? "Not since. Soon as their backs were turned she was so cruel."

Bailey relives her mother's treatment over and over. "My mum was due to go home, they dropped her trying to put her back in bed, she landed on her back. They deny that to this day. It happened on the Saturday night I got there, and on the Sunday morning she couldn't breathe. It took them three days to get a doctor to see her. I went to the nursing station on the Monday night and said please come, she has not been right since she was dropped. At which point Nurse Ratched [Bailey named her after the character in One Flew Over the Cuckoo's Nest] runs along the corridor and is over my mother going: 'Bella you weren't dropped, were you? You slipped didn't you?' I never saw her move so fast."

Bailey speaks to the media after the publication of the Francis report. Photograph: Oli Scarff/Getty Images

Her mother had been admitted with complications from a hiatus hernia. As she deteriorated, a doctor called Bailey and her daughter into a room and said, Bailey claims: "'It's a poor prognosis: your mother is going to die a painful death and she will go just like that' and he clicked his fingers. I said 'under no circumstances am I leaving my mother in your hands'."

After that Bailey, in occasional rotation with her daughter and niece, stayed on the ward full time. "We never upset them. But when the nurses weren't around we would help with the other patients. I made sure I never got in the way, but I might leave a note saying 'so and so has been sick all night and the bed needs changing'. One night I went down to the toilet about two in the morning and they had taken away the chair I slept in. After that they would be slower and slower bringing Mum's drugs around, she would be waiting six hours for a heart pill. [But] there were some wonderful staff. The younger staff tended to run themselves ragged. When I left that ward the morning my mum died, those patients were crying out my name all the way down the corridor. They knew it was over for them once I had gone."

It is perhaps not surprising that Bailey's highly charged account of her mother's time on that ward should have divided the community in Stafford. No community wants to become a national shorthand for neglect. More than 30,000 people marched in the town to prevent the closure of the emergency services at Stafford. "I don't go out here on my own any more," Bailey says. "When I did I would be in Tesco and people would come up in my face and shout: 'Nobody died at that hospital. You are making it all up'." One of the things about Stafford, a county town, Bailey suggests, is that they don't want anything to do with Stoke-on-Trent. "That's the Potteries. The idea of sharing hospital services with Stoke-on-Trent is beyond the pale."

Does she see any prospect for healing the rift in the town? "People need to face up to what has happened first," she says.

When I spoke to Bailey last week she seemed happy to have got away from Stafford. She now lives in her caravan, though she still travels close to the town for meetings. She is pursuing an application for charitable status for Cure the NHS so she might be able to draw a salary to support her work. The process is a slow one, not least because she has to get permission from the NHS to include its name in the charity's title.

Meanwhile, a dozen more branches of her campaign have been established. Bailey has helped to find leaders for each of them. It is her belief that eventually every hospital will have a group attached to it, working to expose any habitual harmful practice and wilful understaffing of the kind she witnessed. "I hope I can just coach them a bit in what I know and let them get on with it," she says. "Your mortality rates are a starting point. But more importantly we would like to see anonymised complaints in the public arena, along with details of serious untoward incidents. Match that with mortality rates and staffing levels and you begin to see a picture."

Over the summer, some of the senior nurses from Stafford, including Heather Gough, who spent 40 years mostly in A&E, have appeared on the radio and TV to dispute the findings of the reports, saying that the failures were a result of overwork and antiquated equipment: "There was poor care in places but it was never intentional." How does Bailey feel about that?

"We were really disappointed to be honest," she says. "Something like 0.2% of the staff gave evidence to the independent inquiry. So it is disappointing that they have come out only now. Our argument was never against all of the staff, it was the system and the management of it."

In the coming weeks Bailey will discover whether her campaign for greater transparency and accountability in those systems will change the NHS for ever. At the end of this month the health secretary, Jeremy Hunt, is due to make his policy recommendations arising from the Francis report. "We told him there is no point giving us the public inquiry if you are not going to implement its recommendations. That would be even worse."

One difficulty is that Francis made an unwieldy 290 recommendations. Bailey would like to see a focus on half a dozen: "Our key priority is safe staffing levels," Bailey says. "We would also want neglect of patients to be made a criminal offence; a system of regulation for healthcare assistants; a legal duty for a manager to take action on an issue of patient safety; fundamental change to the NMC and the GMC [General Medical Council] and the way they run their own disciplinary procedures; and a proper investigation into the gagging orders and payoffs to whistleblowers."

Is she hopeful?

"Well, there are loads of organisations doing lots of really good things since Francis's inquiry," she says. "But what I am worried about are the professional bodies and the unions, the way they have just closed ranks. I can't see why they are not out with banners along with us arguing for safe staffing levels. What more evidence do they need?"

On a personal level, Bailey is pleased to be able to shut her door at night and feel herself safe. "It's a relief to be able to go out on my own again," she says. "I went to buy an electric fire off a gentleman recently and he turned out to be a doctor. I didn't know how he would react, but when he recognised me he just said: 'Oh come here, let me shake your hand'."

• On 26 January 2014, the Observer published the following clarification: "I don't go out here on my own any more", an interview with Mid Staffordshire hospital trust whistleblower Julie Bailey, (New Review, 27 October 2013, page 6) referred to her opponents claiming that more extreme assertions, such as patients being left to drink from flower vases, were lurid media myths. We have been asked to make it clear that the inquiry into failings at the hospital, conducted by Robert Francis QC, did not hear any direct evidence about any incident of patients forced to drink water from flower vases.