There was the rumour that she got a barring order against Bertie. Not true. And there was the rumour about Bertie cheating on her with Celia Larkin, before the marriage ended. No comment. And there was the rumour about her and Bertie getting back together in 2003. Just good friends, they said.

She’s been the frumpy ex of the Teflon taoiseach. She’s been the woman scorned as Bertie travelled the world with Larkin as his official consort. Celia was the mistress in the beauty business, Miriam the matronly mother of the taoiseach’s children. The difference weighed more than an inch or two on the waist.

There are no opinion polls for the wives of politicians. But Miriam has had to face the electorate of newspaper gossip writers more than once — and sometimes the result has been scathing. She is known to have been particularly hurt by unfavourable descriptions of her attire at her daughter Georgina’s infamous French wedding to Westlife’s Nicky Byrne.

The clear insinuation at the time was that she didn’t fit the Hello! magazine mould into which her daughter had married. But this is exactly the type of faux celebrity she rejects. She doesn’t even regard Byrne as a celebrity; he’s just the fella Georgina’s been with since their school days in Baldoyle.

Last week, the social diarists were at it again, only this time they were celebrating the birth of a new Miriam. A confident, well-dressed matriarch was the picture of stylish middle age as she appeared on the set of the Hollywood movie adapted from a book written by her other daughter, Cecelia. One daughter married to a sex-symbol pop star, the other a multi-millionairess and international bestselling author. PS, I’m over you.

Indeed, Miriam is over Bertie. With a long-term boyfriend now in Terry McCoy, who owns the Red Bank House & Restaurant in Skerries, Co Dublin, she’s moved on. Where once she wore the worried weariness of a woman who could never quite escape her marriage to the taoiseach, or separate herself from the persona of the ex, she now exudes a new confidence. Where another 52-year-old mother-of-two might be drowning in the depression of empty-nest syndrome, she has taken on a new independence, socialising with her daughters and embarking on a fundraising career with the children’s charity CARI.

It’s hard to imagine that the 20-year-old Miriam, living with Bertie in a small house in Artane, Co Dublin, in the 1970s, ever thought that one day she would be a lady who lunches. Their nearest claim to fame then was that their next-door neighbour was councillor Joe Burke, now the chairman of Dublin Port Authority.

One of 11 children, Miriam was born into the Kelly house on the Clonliffe Road in 1954. She was an insecure child. She has spoken about irrationally suspecting that she was adopted. She based this suspicion on the fact that she was the first girl born after four boys. She has hinted that she would have liked to have had a closer relationship with her mother, who was loving but not a friend. This distinction could not be drawn in Miriam’s own relationship with her two daughters. Friends, like the socialite solicitor Gerard Kean, say her motherhood is one of Miriam’s defining personality traits.

“She’s a wonderful person, a very impressive individual, and a great mother,” Kean says. They have met at various private dinner parties as well as on the charity circuit and he says the public rarely gets to see the real Miriam Ahern.

“I don’t think a lot of people know what a great sense of humour she has. I’ve had plenty of great times with her. She’s great to be around. She has this tremendous laugh, a real throaty laugh. She knows how to enjoy herself.

“She’s not someone who’s cracking jokes, but if you’re in company and telling a story, she is one of those people who really enjoys it. You see her with tears in her eyes, she’s laughing so much. She’s a very engaging woman, intelligent, discreet — a bit like Norma Smurfit.”

Miriam is certainly discreet. She has never dished the dirt on Bertie, despite numerous opportunities. She told Ryan Tubridy that their separation was difficult. Political observers, particularly those close to the Drumcondra Murphia, understand that the separation was more than difficult, and was in fact acrimonious.

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