“I’m still hoping. I can’t really believe it’s going to happen, but in the back of my mind it’s always there. I love this country; I want to live here. I always dreamed of coming, because it was such an open-minded, lovely place where foreigners were greeted. I think that’s part of why I was so shellshocked on 24 June: because this country I thought I knew suddenly turned up a very ugly face.”

Chris Hoffman is a 44-year-old freelance translator who lives in south Birmingham. She is originally from Stuttgart and first came to the UK thanks to the European Union’s Erasmus student exchange programme. Later on, her husband started academic research in Birmingham, which then turned into a full-time job – and a little more than a decade ago, they settled in the city. They have an eight-year-old son. “He might not have a British passport,” she tells me, “but he was born here, and he feels British.”

Now, the prospect of Britain leaving the EU seems to have infected her life with anxiety. Does she think she might have to go back to Germany? “We’ll have to, if they chuck us out,” she says. “We haven’t got EU residency cards; we haven’t gone for naturalisation.”

Why not do that? “If the government starts throwing out EU citizens, I don’t want to live in this country any more,” she says.

On the first working day after the Christmas break, Hoffman has arranged to meet me in a cafe in the Kings Heath area of the city, along with two people who are campaigning alongside her against Brexit: 55-year-old Margaret Murray, who came to Birmingham 30 years ago from Ireland; and George Turvey, a native of south Wales who was, until recently, employed at Birmingham City University, but is now devoting his working time – on an unpaid basis – to trying to keep Britain in the EU.

The three of them are among the 15 people behind EU in Brum, an amazingly active set-up that was founded in the days after last year’s referendum. None of them did any formal campaigning prior to the vote; they fully expected the leave campaign to amount to nothing more threatening than a sizeable protest vote, and for remain to convincingly win. Late last year, EU in Brum was also the host for a “national grassroots remain strategy meeting”, organised by the new national pressure group Britain for Europe, and intended to coordinate the work of a whole host of campaigns.

Chris Hoffman during a pro-EU rally in Birmingham in October 2016. Photograph: Jane Campbell/EU IN BRUM

“There were about 40 organisations there,” says Turvey. “More dialled in on Skype. We had somebody from Gibraltar. There are a lot of expat organisations – people who travel from France and Germany to the meetings. It’s about collaboration, how we can work together, and grow the movement. We’re all linked now, and there’s work going on all the time.”

And what is their main objective?

“Remaining in the EU,” he says. “Of course.”

Some former remain campaigners, I remind him, are now seemingly resigned to Britain leaving the EU, and set on pushing for what political cliche calls a soft Brexit. How does he feel about that?

“We’re unequivocal; 100%,” he says. “We’re not going to compromise.”

The Conservatives are combining a rush towards the European exit door with the sense that they have no real negotiation plan. As of Tuesday, when great howls of dismay went up from left-leaning remainers, Labour’s position combines Jeremy Corbyn’s claim that “the UK can be better off out of the EU” with a possible watering-down of the leadership’s support for the principle of free movement, suffused with the increasingly familiar sense of a party that is all at sea. So, while the SNP remains staunchly pro-European, it’s not surprising that, in England and Wales, people who passionately want Britain to stay in the EU feel they are not represented (apart from by the Lib Dems and Greens, perhaps – but with 10 MPs between them, that might amount to rather cold comfort).

In response to this growing political gap, initiatives aimed at fighting Brexit and somehow overturning the referendum result have been springing up in huge numbers. Besides EU In Brum, there are plenty of groups rooted in specific places: Aberdeen for Europe, Hants4EU, The Berkshire 48%, Glostays, Wessex for Europe, and many more. Online, you can choose from such national networks as Britain for Europe, Sixteen Million Rising, Vote for Europe and Want2Stay.

A somewhat secretive set-up called EU Flag Mafia – whose people do not answer my enquiries on Twitter – has been founded with the aim of making sure the EU stars are seen as often as possible: back in September, they distributed around 2,500 EU flags at the Last Night of the Proms. March for Europe organised two anti-Brexit demonstrations in London last year, and another one, overseen by a network called I’m Still In, is planned for 25 March. On 20 February, people will be involved in One Day Without Us, an attempt to highlight the contribution immigrants make to Britain via special events – or by simply not turning up for work – that will have a big anti-Brexit dimension.

As much as anything, this burgeoning resistance highlights what an insanely divided country the UK has become. Post-referendum conversations with convinced leave voters usually include unshakable views that have now hardened into cliche – chiefly, the idea that even now, we are only a few establishment manoeuvrings away from some great stitch-up that will overturn the result. And guess what? In the eyes of people who want out of Europe as soon as possible, that might be exactly what the anti-Brexit activists are aiming at.

The latter, of course, say that a minority of the overall electorate voted to leave and that there is hardly the thumping mandate for leaving Europe some politicians talk about – and that, besides all that, Brexit will be such an economic and social disaster that it has to be avoided.

Whatever, were you to put both camps together, there would be precious little common ground – which is perhaps why a lot of people talk about what George Turvey says is now very common – “the breaking-up of friendships, even rifts within families.”

For the people involved in the anti-Brexit movement, it is currently pretty much impossible keeping up with who is doing what, but what is happening is a prime example of how 21st-century politics increasingly works. The lumbering structures of parties and traditional top-down pressure groups are ill-suited to such a spontaneous upsurge. In any case, the fact that mainstream politics is barely representing anti-Brexit views has encouraged people to simply do something themselves, only to find that thousands of others feel the same way.

The day before my trip to Birmingham, I take a train to Manchester to find out more about one of the most vocal national anti-Brexit organisations – 48 And Beyond, which is a hyperactive force on Facebook, and is set on encouraging the formation of yet more local anti-Brexit groups. Its founder is 32-year-old Eoin Ward, originally from Omagh in Northern Ireland, who is studying for a masters while also teaching English as a foreign language to, among other people, students from EU countries whom he says are now facing a very uncertain future.

We meet in a city-centre Pret a Manger, where he explains both his own staunch belief in the EU (partly down to where he’s from: “People in Northern Ireland see the EU in action every day,” he says), and the six-month story of what he started the day after the referendum.

At that point, he says, he had done “a bit of leafleting” with the official remain campaign, and was expecting a narrow win for his side – but when the unthinkable happened, he very quickly resolved to take action. On 24 June, he recalls, a group of English friends of Irish descent paid him a visit: “They had just been to the Irish Centre in Manchester to get their Irish passport forms; they were getting in there early. We sat and sympathised for a while, and then we said: ‘We really need to do something.’ So I started a Facebook group called The 48%. I invited about 30 Facebook friends to join. That was on the Friday afternoon. By Sunday evening, we had 20,000 people.”

The group is now closed (in the sense that permission has to be given for people to join), and has more than 50,000 members; its Facebook community page has 30,000. There’s a steering committee of four people which does a video conference every Tuesday and meets up “every now and again” – but Ward says the group’s priority now is to manifest itself in the offline world. “We’re trying to get people off Facebook and out into their local area,” he says. “That’s a big push. Reading for Europe was the first; he says that Manchester for Europe is now close to hitting 200 members. So how many local offshoots does he think 48 And Beyond have spawned? “At least 50,” he says.

Eoin Ward (right) at a 48 And Beyond rally in September 2016. Photograph: Eoin Ward

Campaigning, of course, comes with risks. In August, Ward was involved in organising a pro-EU demonstration in central Manchester. “At least 20 quite scary-looking people turned up with bandanas over their faces, holding up St George’s flags and filming everything. I don’t know what group they were from but, to me, they looked a bit kind of neo-Nazi, white supremacist – that sort of ilk. They were giving us a lot of grief, telling us we didn’t respect democracy.” What about online? “We sometimes get leave voters infiltrating the group, writing quite provocative things. But it’s water off a duck’s back. It’s much scarier in real life.”

What is his basic aim? “What we want, first of all, is for Theresa May to acknowledge that there are 16 million people who voted remain, and represent those people to some degree. So far, she has ignored almost half the country. At the moment, we don’t feel represented, and I think that’s why there are so many groups.”

Is he trying to overturn Brexit?

“Initially, I did say: ‘We will try to stop Brexit.’ I personally think we’ve gone too far down the line now. I’m not saying that’s the view of all the people in my group, but it seems like we’re on that path, with the deadline for article 50. And I’ve always been for the best possible deal for the people who voted remain. That means no change to employment protection, environmental protection, or free movement – all of those things we like about the EU. We don’t want those to change. Being a member of the single market? No question.”

And can he and the group make a difference? “Definitely. What’s the alternative? Just sitting back and accepting everything? We’ve got to at least try.”

EU in Brum had its first meeting about two weeks after the referendum, in the upstairs room of a cafe, where around 40 people showed up. At first, their conversation was more a kind of collective therapy than political action. “People were traumatised,” says Margaret Murray. “I think they wanted that space to meet other people who felt damaged, whereas within their own families or at work or wherever, they couldn’t express those things. Some of them felt like, ‘I don’t know the people around me any more.’”

Now, though, EU in Brum is all about being visible, and loudly making the case for Europe. It holds fortnightly public meetings, does regular street stalls, and makes a point of showing up at any number of local events, from last summer’s Labour leadership hustings, to gatherings of local businesspeople. In September, it held its first march in the city centre, which attracted around 500 people, who were guided around a route taking in buildings that would have been inconceivable without EU funding. Not long after that, the group arranged another rally outside last year’s Conservative party conference, at the city’s Symphony Hall – ironically enough, the centrepiece of a development that was assisted by £50m funding from Brussels.

Three months on, the group still think that Brexit can somehow be overturned. “I think we still have every chance of achieving that,” says Hoffman. “It’s probably not going to be easy, but I don’t think it’s set in stone that we have to leave.”

“Theresa May could just turn it around,” says Turvey, who emphasises the constitutional fact – perhaps offset by the politics of Brexit – that the vote was advisory. “There’s no reason why she has to pursue this headlong crusade to ruin the UK.”

“There are many ways it could happen,” says Hoffman. “If you have a second referendum, or a general election … More and more, remainers are in the news, and people realise that this is still an ongoing topic. People are saying: ‘Maybe I voted leave, but I’ve had a rethink.’ I have met several leavers who now regret voting that way.”

The message is simple: a protester at the March for Europe. Photograph: Anadolu Agency/Getty Images

What about the idea that a lot of people and places that voted leave did so after years of feeling completely marginalised – and that, if they were ignored again, their resentment would turn nuclear?

“That is one of the major issues: this sense of alienation and isolation in society,” says Turvey. “If people wanted to take advice from this advisory referendum, there’s a key piece of information. But the government is doing nothing to address it. That’s what they should be doing.”

There is one last devil’s advocate point. When leavers talk about the EU’s democratic shortcomings, or its embrace of the economics of austerity, they have a point, don’t they? Is it really an institution worth defending with this much passion?

“We pay less than 0.5% of our GDP to the EU,” says Turvey. “Think of all the incredible benefits: some research came out saying that we maybe get 5 or 6% of our GDP back, from the fact that we’re a member. If you weigh that against the fact that there needs to be reform, and we could make it better … the UK was a leader in the EU, and it should still be at the heart of it, making sure it is strong and fit for purpose and the best it can be. And the other thing is, what’s the alternative? It’s just a no-brainer.”

Which brings us to perhaps the most interesting question of all. Can the resistance movement not merely sustain itself, but actually grow?

“It’s getting bigger all the time,” says Hoffman.

“It is,” agrees Turvey. “And, really, it’s only a matter of time. There’s never been a good-news story for Brexit, has there? It’s all negative. If you look at the prospects for the UK, it’s disastrous.” He has been remarkably upbeat for the past hour and a half, but suddenly he almost seems to light up. “Surely, soon enough, people will have to realise that.”