Forget The Six Million Dollar Man, bestselling author Deborah Moggach is the Hundred and Thirty Six Million Dollar Woman. Worldwide box office takings for The Best Exotic Marigold Hotel, adapted from her novel These Foolish Things, wildly surpassed expectations, making it one of the biggest hits of last year. Now her new book, Heartbreak Hotel, looks set to garner more accolades for a prolific novelist and screenwriter at the top of her game.

Just as Marigold Hotel revolved around a wonderfully original idea – the outsourcing of elderly Brits to India – so Heartbreak Hotel breaks new ground with its portrayal of people coming to terms with lost love. The story unfolds in a Welsh B&B. But this is no ordinary guesthouse; it’s a school for the broken-hearted.

‘Our lives are changing,’ says Deborah, lighting a roll-up and perching on the sofa in her house overlooking Hampstead Heath, North London. ‘Most people used to have one marriage that lasted for life, but nowadays we’re living much longer so we often have serial relationships. Many of us have two or three big loves during the course of a lifetime and that means more endings. The challenge – and the theme of the book – is: how do we cope with those endings?’

As with The Best Exotic Marigold Hotel, which offered a pragmatic (if delightfully romanticised) solution to the problem of retired folk eking out dwindling resources, Deborah’s new book also demonstrates a practical bent to her thinking.

‘Usually, in any relationship, one person assumes responsibility for one set of tasks – the cooking, say, or the car – while the other tackles the rest – the finances or the DIY. But when a couple splits up, or one partner dies, it can feel horribly disempowering to discover suddenly that you don’t actually know how to change a plug, or book a holiday, and that adds to the feeling of hopelessness.’

And that’s where a sojourn at Heartbreak Hotel could make all the difference. Run by retired actor Russell ‘Buffy’ Buffery, the B&B becomes an emotional pit-stop where bruised souls can swap practical skills while gathering the strength to pick themselves up, dust themselves off and start all over again. Among the ‘Courses for Divorces’ offered to male guests is thrice-divorced Buffy’s own tutorial: How to Talk to Women.

‘I think a lot of men still find it incredibly difficult to relate to women,’ says Deborah. ‘Blokes are inclined to talk about things, whereas women are much more interested in feelings. I remember a friend falling in love with a woman and whisking her off to the Black Mountains for a camping weekend (not the most romantic idea, but men can be funny that way). When he came back, all his friends were dying to know how it went and he told us at great length about how he’d slept in a wonderful triple-sewn, Arctic-weight sleeping bag, – no doubt very snug but way down the list of things any of us actually wanted to know. And that was such a male answer. No woman in the world – especially one who’s just got off with a new bloke – would tell you about the type of sleeping bag.’

It’s a typically acute observation from one of our sharpest-eyed chroniclers of the battle of the sexes, but it’s not meant as a dig at men.

‘I think it’s a ghastly time to be a man,’ says Deborah. ‘Women have become so demanding, so powerful, and often make blokes feel redundant. Men nowadays are constantly told they need to be “in touch with their female side” – gentle and considerate as well as manly and powerful. It’s almost impossible. And when they do their best to be nurturing and lovely, their wife or girlfriend rewards them by running off with the plumber or builder, someone who’s a dab hand around the house. No wonder so many men are dazed and confused.’

‘Dazed and confused’ is the perfect description of Marigold Hotel’s Douglas Ainslie, the long-suffering husband played in the film by Bill Nighy. Will we be seeing Douglas again, along with Dame Judi Dench’s merry widow, Evelyn, and Dame Maggie Smith’s waspish Muriel? There’s talk of a sequel but Deborah won’t be involved.

‘I’m all written out on that particular subject. But the film was such a success partly because it catered for a group of people often ignored by Hollywood executives. They don’t understand that there are masses of older, discerning cinema-goers who want films that speak to us about our own situation.’

Has exploring issues that crop up in later life made her think about her own ageing process? ‘Absolutely not,’ she laughs. ‘I don’t want to think about it at all. I’m 64, surrounded by people my own age, and my goodness, they moan! We’ve all got bits dropping off all over the place, but we don’t need to bang on about it all the time.

‘I was arranging to see friends recently and the woman said, “I’ll phone you before we meet and tell you all the things that are wrong with me and my husband – his cancer, my hip replacement, etc – so we can get the dull stuff out of the way and just have a jolly dinner”. I love that approach. We’re all facing difficult things, but there is so much interesting stuff in the world and I think we should focus on that.’ She laughs again, this time at herself. ‘In other words, I’m totally in denial.’

In 1985, Deborah’s mother, Charlotte Hough, also a writer, was imprisoned for helping a desperately ill friend commit suicide. ‘It’s still hard to believe it happened,’ says Deborah. ‘Parents occupy a certain place in our heads, so to visit her in prison and see her suddenly so vulnerable and being ordered about by a meaty, key-jangling prison officer was very upsetting.’ Is she tempted to write about the experience? ‘No,’ she says firmly. ‘It was my mother’s story, not mine.’

She has, however, written about another harrowing episode in her own life. In 1994, her partner of ten years, the celebrated cartoonist Mel Calman, died of a heart attack while they were watching Carlito’s Way at the Empire Leicester Square. ‘It was deeply traumatic. I spent weeks at home, drinking sweet tea and smoking roll-ups, incapable of doing anything. Grief is like childbirth: you have to concentrate on it very hard to get yourself through it.’

Three months later, she fell in love again, this time with a Hungarian artist 17 years her junior. ‘It was a period of extraordinarily heightened emotions – coruscating one minute, wonderful the next. But I didn’t feel I was betraying Mel at all. It was a completely different sort of love affair, and he would have wanted me to be happy.’

When the relationship finally ran its course, Deborah spent several years hacking her way through the dating jungle. ‘No matter how old we get, it’s the same old teenage heart beating inside. You’re wondering if he’ll phone. How many XXXs in his texts? But some aspects of being Out There as a singleton have definitely changed for the worse. I was once set up with a much older man. We went to the theatre and I paid £80 for the tickets. He reciprocated by taking me to a Chinese restaurant, which he said was his favourite because it was the cheapest place in town. So we sat in this grim, strip-lit, all-you-can-eat-for-£5.99 restaurant and he proceeded to take out his false teeth, then masticate his gummy way through a bowl of soup filled with tiny shiitake mushrooms.’

Undeterred, Deborah persevered with the dating merry-go-round and is now happily settled with a new partner her own age. ‘Falling in love is always full of turbulence, no matter how old you are. When it comes to matters of the heart we’re all still 15, but we now come with lots of extra baggage. When you get to this stage of life, being with a new partner of the same age somehow mirrors your own mortality, which can come as a bit of a shock; but it’s also very companionable to be a bit saggy together, and to share frames of reference with someone who knows who Alma Cogan was, or Cliff Michelmore.’

With a new romance, the new novel (a BBC One adaptation is in development) and two new grandchildren, it’s tempting to see everything in Deborah’s garden as rosy, but she’s anything but smug or complacent. ‘I’m lucky at the moment,’ she says, ‘but life is so rocky and fragile, everything could fall apart at any second.’

And in a parting shot, as if wary of tempting fate, she produces a clipping in which an agony aunt addresses the wife of a faithless husband. ‘As a mature adult, you’ll know that our emotional lives are lived out in a perilous playground, far removed from early fantasies of eternal love and ideals of right and wrong.’

‘Brilliant!’ she says, laughing again. ‘If you ask me, that says it all.’

(Interview taken from Saga Magazine online: http://www.saga.co.uk/saga-magazine/2013/february/deborah-moggach.aspx?pid=mn)