What Katie did next: Is the star formerly known as Jordan thinking of stepping out of the limelight?

Where to begin? Well, she is clutching at her stomach in a maternally protective fashion right now, so why not here? Katie Price, formerly the glamour model Jordan, and still confoundingly one of the country's most famous women, is telling me about her latest pregnancy (her fourth), and does so in a typically Katie Price kind of way.

"No pap has got a bump picture yet," she says, beaming with pride. A pregnant Price represents high currency for any self-respecting paparazzo, but she explains she has been hiding herself away these past six months, busy with pregnancy matters, and arranging all her latest endorsements: her perfume, her shoes and handbags range, her wedding dresses. She has two books looming, a novel now, and her latest autobiography in October. I ask when the baby is due, but this is met with another uniquely KP response.

"I haven't given the due date to anyone yet, and I'm not going to," she states, the due date being privileged information with which, were she to let it slip, I could do – what, exactly? Sell it as an exclusive to Heat magazine? Perhaps. Anyway, if it really is privileged information, she isn't guarding it particularly well. She has already confessed to having deliberately hidden herself away for much of 2013, which presumably means she's been expectant as long. An autumn baby, then. But surely Heat knows this already?

If it does, then it hasn't come from her. "I don't read those trashy magazines any more, and I don't give them interviews," she says. She used to, all the time, but now she is determined to establish some kind of normal life, with boundaries. Because of this self-imposed silence, however, "They make up all sorts of rubbish about me all the time."

More rubbish is likely to be flung her way soon enough. Price is currently in litigation with her former husband Peter Andre and his management company Can Associates, seeking the return of "private data" which she believes they are planning to use to harm her reputation. She tells me she can't say too much about it, but then speaks freely nonetheless, and less than complimentarily, about Andre and his conduct. Beside her, her PR Diana winces. Price has been forced to pay out libel damages to her first husband before, in 2009, after claiming he had been unfaithful. But she either doesn't remember this, or doesn't care. Diana does. She calls me the next day pleading that I don't quote anything Price said about the forthcoming trial, because it will just make an already complicated case more complicated still.

"It's a stressful time," Price says to me now, shrugging, "but, you know, whatever."

We meet in inauspicious surroundings: her management offices in central London, in a room the size of a holding cell. It's a warm day, so the window is thrown open to the lunchtime heat. Price is dressed in a billowy cream blouse – that covers not only her bump but her famously pneumatic breasts – black leggings and a pair of faux (possibly) snakeskin hi-top trainers. Her hair is long and straight and jet black, and her face is make-up free and, consequently, prettier than it ever seemed on her reality shows. Her pale green eyes are stunning.

She is, in the flesh, entertaining company, brash and blunt, and winningly frank. "I talk a lot, don't I?" she says. She does. The woman simply cannot edit a single thought, which is probably why Diana is sitting beside her, to edit for her. (An example. Price, to me: "I'm a binge drinker." Diana, fearing subsequent headlines: "Katie, you are not a binge drinker.")

We are here ostensibly to talk about her new novel, He's the One, a piece of romantic fluff about a 20-year-old single mother who waits tables before becoming a Hollywood sensation, then, years later, returns home to the realisation she is still pining for her first love. It will of course comfortably outsell almost everything else in Waterstone's; her novels always do. "This is my 49th book," she says. Diana points out it's her ninth novel. The vast remainder are her various autobiographies, her children's books, and her equestrian titles. Price has now sold more than five million books in the UK, making her one of the country's most successful writers.

"Even Kieran didn't know I'd written so many," she says. Kieran is Kieran Hayler, her current husband. They met late last year, married in February; the bump is his. "He came into my office one day, saw them all on the shelves and said to me, 'I didn't know you wrote all them books!'"

There is routine ridicule in the broadsheets over Price's literary achievements, one could say unavoidably so. Her novels are ghostwritten to a fairly strict wish-fulfilment formula, while her tell-all autobiographies are "just me talking into a Dictaphone" – before the lawyers wade necessarily in. It is difficult, critically speaking, to detect much in the way of merit in her work, but she clearly has an audience, which is more than most writers have. She wants to get into crime next – "But the real stuff, nothing made-up."

She loves true-crime tales about serial killers, paedophiles, rapists. "If I could go into a prison and interview a real serial killer for a book…" Her eyes are Lottery-winner wide, "…That would be my dream job."

At this point in our long association with Price, we surely know everything there is to know about her. Every aspect of her life, since the age of 17 and her first Page 3, is played out in public, paraded on TV, the tabloids and those trashy magazines she no longer talks to. She is loved and loathed, and endlessly derided, but also increasingly respected as an undeniably shrewd businesswoman. As the quintessential modern celebrity, her backstory is the quintessential modern fairytale, intriguingly skewed and with its quota of thorns.

It started back in 1996, when she first bared her breasts in The Sun, a modest 32B which she then inflated into basketballs that made her, and them, infamous, before undergoing a series of reduction treatments. Then came the car-crash relationships with pop stars and football players, her liaison with one of the latter, former Manchester United player Dwight Yorke, resulting in her first child, Harvey (Yorke demanded a DNA test, just to be sure). Harvey, now 11, was born blind, with a condition called septoe-optic dysplasia, and was later diagnosed autistic. She is furiously protective of her son, rightly so, and regularly features him in her reality shows for what she insists are sound reasons: "It's important to talk about living with, and coping with, a child with disabilities. I've checked with his teachers, his school, and they all agree."

In 2004, she officially retired Jordan, went on to I'm a Celebrity Get Me Out of Here, and re-emerged as Katie Price, a bawdy Barbara Windsor-type who, while in the jungle, fell in lust with the long-forgotten Australian pop star Peter Andre. They married, more quickly than seemed sensible, and her association re-ignited his fortunes in an instant. They landed their own ITV2 reality show, and produced a couple of children they named Junior Savva Andreas (born in 2005) and Princess Tiaamii Crystal Esther (2007). Then they split, acrimoniously.

"There's a thin line between love and hate," Price says tartly. "I realise that now."

Next, she did what any reality-TV star worth her salt would do: met and swiftly married a cross-dressing cage fighter with stars in his eyes. His name was, and likely remains, Alex Reid, and he essentially became the new Peter Andre, riding on his wife's coattails, first into her TV show, then in one of his own (which she tells me she arranged), before everything soured and they separated.

"My second marriage was a total rebound, I'll admit that now," she says. Turning to Diana and referring to her forthcoming autobiography, she says: "Just you wait till you read what happened. It's all in there. It's disgusting, what I had to put up with."

So why, I ask, did she marry the man? She shrugs. "Because being in love is a good thing, and because I fall in love quickly. I take risks."

Which also provides a likely answer as to why she is now married yet again, to Hayler, a plasterer and part-time stripper. At 26, Hayler is nine years his new wife's junior, and stepfather to her three children, "but I don't push them on him. They already have their father – Pete – although Pete hasn't seen Harvey for a year now…"

She insists that Hayler is a real man, a suggestion that her previous husbands weren't.

"He's up at 5.30 every morning, on the building site by six, and every Saturday night he's out stripping." But upmarket stripping, on a stage, all respectful and proper. She makes a point of telling me that his stripping is not the kind that takes place in sweaty pubs where women in the crowd try to grab any stray penis that comes their way. "No way! I wouldn't allow that." Kieran does get his "willy" out, "but only for 10 seconds at the end. And no touching allowed."

Many might find it curious that a man married to a woman worth £45 million feels it necessary to work at all, but Price is adamant that this is the way it has to be.

"It's what will keep us together. It's a shame, in a way, because he is lovely, and I want to spoil him, but I've said to him that I've been taken advantage of so bad in the past that unfortunately he's going to get fuck all from me."

Katie Price is 35 now, ancient for a glamour model, and a good decade older than any of those tantastic twits on most reality-TV shows. She is acutely aware of this, she says, which is why she is taking a concerted step back. There will be no more ITV2 shows, but instead she will have her own YouTube channel to continue documenting her life, albeit with much more editorial control and, perhaps, more prurience.

"When I was married to Pete, I don't know what I was thinking. Everything we did was documented, every party, every trip, on the telly, in magazines. It's not healthy."

It's begun to have a detrimental affect on her children, too. She says Junior, aged eight, is already obsessed with the limelight. "He wants to go on Britain's Got Talent; he wants to present Jeremy Kyle; he wants a Lamborghini. He keeps telling me he's famous, and I'm trying to tell him that just because his father puts him on his TV show, that doesn't make him famous himself."

She has plenty more to say about Andre's approach to fatherhood, but it is this that Diana wants omitted here. The gist is that Price, in pursuit of brand longevity (and familial sanity), wants to take a step back, and no longer parade her soap-operatic life in full view of the public's perpetual gawping – though she promptly appears to contradict this when she tells me that she is currently considering an offer to appear on this summer's Celebrity Big Brother.

Either way, she has recently moved from one greenbelt country mansion to a more remote one that sits within 52 acres of private land inaccessible to even the most persistent paparazzo. "I can stand in one of my fields stark naked if I like, and go WAAAYYY!!!, and no one would know."

But could Katie Price really continue to exist without the oxygen of publicity? It seems unlikely, but she insists she can. She says she is no longer bothered about being famous, and that rather than being a staple of the gossip columns, she wants to establish herself on the lecture circuit (she has already spoken at Oxford and Cambridge) talking about business sense, and how to maintain a long-term career. In order to maintain her own, she will offer up her rollercoaster life to the public in bite-size chunks only.

Frowning, she says: "People would get bored otherwise." Which is, of course, the one thing she cannot allow to happen.

'He's the One' by Katie Price is published by Century, priced £16.99