As Nicola Barker admits, her new novel, H(a)ppy, “really does mess with you in the end”. About halfway through, she reckons, is where “it gets nuts”, but to be truthful, the signs are there from pretty early on. Here’s a quick precis, with no spoilers. Set in a future saved from floods, fires, plagues and death cults by “the Altruistic Powers”, it’s the story of Mira A, a member of the Young – a generation freed from uncertainty, desire and emotional unevenness by constant regulation of the Information Stream and minute adjustments to preserve the balance of the Graph.

But that’s only the half of it: on the page, type breaks up, symbols and pictures form themselves in the gaps, fonts jostle, and change case and colour to indicate a shift in the intensity of mood. A second story – that of the history of Paraguay and in particular the classical guitarist Agustín Barrios, whose work Barker suggests listening to as an accompaniment to the book – begins to intrude, much to the consternation of those keen to keep Mira A and her neuro-mechanical pet dog on an even keel.

In this brave new world, God has gone, there is no more recorded time and narrative itself is taboo. Narrative, Barker tells me as we sit in the riverside flat in east London to which she’s in the process of bidding farewell, is what she uses to make sense of the world and its vast mysteries, and yet here in the novel “the story itself is the destructive element. The thing you’re reading is the thing that’s not permitted. So the words themselves are a breach of something, the telling of the story is what’s wrong, and the urge to tell it is what continues.”

But this is more than an experiment in form, a writing exercise designed to divert and wrongfoot both novelist and reader. She concedes that H(a)ppy is recognisably a Barker novel: the disrupted and interwoven storylines, the sense of disorientation and mischievous playfulness that we’ve seen in novels from the Impac-winning Wide Open to the Man Booker-shortlisted Darkmans and her bravura tale of golfing mayhem, The Yips. However, she insists that it has come from a very different place.

She experienced, she says, “a kind of internal combustion”, an excess of energy that has been both destructive and creative. After she finished her last novel, The Cauliflower, the story of a 19th-century Indian mystic, she almost immediately began writing H(a)ppy, “which was not what I wanted, but I just did it because of what came to me”. She entered a period of profound insomnia, sleeping hardly at all “but really cheerful”, constantly working, whether at writing or more mundane tasks (“I don’t really understand people who aren’t always doing chores”). She had overworked, she knew, for quite a few years – she is 51, and this is her 12th novel – and now seemed almost on the edge of mania. At the same time, her decades-long relationship with the writer Ben Thompson came to an end, although the couple remain close. She found herself in that patch of midlife where, assailed by physical, mental and emotional changes, the figure of one’s teenage self comes into view, and “you look back at them and you just feel a kind of joyful recognition”.

It was, in other words, all change, what Barker describes as “a kind of catastrophic urge that expressed itself in writing, a chaotic urge, but also a joyous one, and a destructive one. I felt I had to embrace it. And when I was writing the book, I realised that the book was going to explode into my life, and it did. Creativity for me has to be that way.”

In terms of her writing life, that left a lot to be negotiated. “I’m not destroying narrative for everyone, I’m destroying it for myself,” Barker explains. “Which is disastrous for me, because obviously I understand the world through narrative. When you destroy the thing that explains everything to you, then what is that process? What have I done? So the last year has been trying to understand why I did that, what it means for me. But also what it means in terms of the novel, because I’ve sort of deconstructed the novel to such an extent – what is left of it?”

Should this make Barker sound solemn, theoretical, obscurantist – even po-faced – she and her books are anything but. In between talking about the death of narrative, we discuss her love of TV bridal show Say Yes to the Dress, which she watches from her exercise bike, Keeping Up with the Kardashians and Big Brother. Both in conversation and in her work, she is fascinating on popular culture, which she views as an enthusiastic bystander rather than a de haut en bas analyst. She used to watch Love Island, she says, but stopped when it became so fixated on sex, and hence duller: “Having been something that was about actual emotions, it’s now become about posturing, the dance of emotions rather than the fact of them. I think reality’s increasingly about form rather than content.”

Unlikely as it might sound, the preoccupations and obsessions that resound through her work – the idea of transcendence, of the relationship of the sharply felt self to an amorphous whole, the phenomena of faith, martyrdom, suffering – are also present in mass culture. “This isn’t just something I choose to be interested in, it’s something I love,” she insists. “If I watch the people on Big Brother being idiots and trying hard and making mistakes, I feel incredible warmth and love for them. It’s really important to try and extend this love and joy everywhere. I hate snobbishness. I find the most interesting and complex things in really unpretentious places. I’m always saying to people, I’m not actually an intellectual. That’s not how I see the world. I am actually quite a simple individual.”

‘I’m always saying to people, I’m not actually an intellectual.’ Photograph: Sarah Lee/The Guardian

Part of this, she thinks, comes from having spent a portion of her childhood in South Africa, “where there is no class. There is race, and difference. And the unfairness of that, and the sense of disjunction that I felt, even as a small child, the sense that something didn’t make sense and it was wrong.” Born into a working-class background, she is now firmly middle class, but maintains an indifference to the subject, and to anything pertaining to writers or writerliness: “That’s not a stance, it’s just: I’m not interested. And so I find books about middle-class people, or books about writers – I just feel like stabbing myself and dying, because I’m so bored.”

Friendly and warm, but not exactly what you’d call clubbable, Barker doesn’t often find herself in the company of other novelists, but she did last year, on a British Council trip to Russia. She had a wonderful time, got on well with everyone, but nonetheless realised that “I was quite different to the rest of them”. What does she mean? Whenever they spoke, she replies, they seemed to talk about how important inclusion and the creation of space for the reader were to their writing process. “And I was thinking, well, that’s not what I do. I create an entire world, and I try to be inclusive because I try to write things simply and seductively, but at the same time the reader has to accept that they’re entering a different world. They can’t just say, there’s room for me here – they have to trust me and come with me on this journey into this closed world.”

In between talking about the death of narrative, we discuss her love of TV bridal show Say Yes to the Dress

A bit like Dante, I suggest: you can come to the underworld but don’t complain if not everyone’s nice? Barker roars with laughter. “It’s not about comfort for me. It can be fun, but I don’t think everything should be easy.” Some of the writers she most loves – Thomas Mann, for example, or Henry James, who she notes provokes fury in the reader by writing such inhospitable sentences – have been “generally obstructive and complex”. Once again, though, this is not a question of effort for effort’s sake, but more closely connected to her quasi-religious sense that “struggle and suffering are some of the most beautiful things”.

Barker comes from a Catholic background and describes her greatest interest as the inexplicable, insisting that “meaning to me comes from beyond knowledge”. Right now, she is aware that her desire to interrogate faith and how it intersects with modern life puts her at the heart of current debate, but at the same time makes her thoroughly unfashionable. “We’re in a society that thinks entirely about faith,” she argues, “because of our sense of encroachment by Islam, and our defiance against that because we have our own way of being, which of course is based in Christianity. But no one is Christian. So we’re trying to defend an ideal which we can’t really define ourselves, which we almost entirely don’t believe in. And we’re coming up against something which is quite overwhelming and encroaching and dictatorial – some aspects of Islam – and yet at another level, there’s something so beautiful and glorious about it. And so I feel as if this conflict is entirely about faith, and yet the one thing no one wants to talk about is faith.”

In her novel The Yips, she continues, she discussed the issue of Muslim women wearing full-face veils. “That was because I found it really difficult encountering women in the full veil in the streets around here, and it used to make me feel uncomfortable, especially because of my deafness [Barker is partially deaf]. If I can’t see a mouth, it makes me uncomfortable. And yet at the same time I knew there was something in me that found it beautiful. It’s that contradiction always in my work and in the way I think about the world that brings the most beautiful and transcendent moments.”

It’s vital, she insists, to constantly pick away at what you’re really thinking and feeling – to refuse to shy away from it, and to accept that it may be contradictory and confusing. Barker is perhaps one of the most vibrant examples of a contemporary artist who refuses to be deflected from her work, or to make compromises in pursuing her aims. Although, she admits, she did have to cede ground on the novel’s title: that bracketed (a) was originally going to be upside down, to indicate that all was not hunky dory in Mira A’s world, but so fiddly and expensive was the book’s design that something had to give.

“You can’t conceive of how many problems I’ve generated in this book!” she laughs, but actually, I can. Many years ago, I published a short story of hers in Granta magazine. It was entitled “The Burley Cross Postbox Theft”, and went on to become the title piece in a book, one of the more comic, shorter novels with which Barker intersperses her longer works. The story consisted of a letter, written by an angry resident to a public official, concerning the disposal of canine excrement. It became madder and madder. It also contained precisely 100 footnotes, each of which had to be carefully positioned for maximum effect. Extreme layout challenges are hardly the stuff of high-end creative endeavour; nonetheless, it’s a testament to the brilliance of that piece of writing that computers and proofs were not ejected from windows. But that’s the thing with Nicola Barker: once you’re on board for the ride, there’s no getting off.

• H(a)ppy is published by William Heinemann. To order a copy for £17 (RRP £20) go to bookshop.theguardian.com or call 0330 333 6846. Free UK p&p over £10, online orders only. Phone orders min p&p of £1.99.