It's a tale of two Irises. There is Iris Robinson, dutiful wife and committed Christian, quoting scripture and denouncing the sexual immorality of others. And then there is Iris, the woman who walks on the wild side, takes a teenage lover, and craves the forbidden fruit.
In all the years I've known her, there was always this internal struggle. Sometimes, she'd say she liked nothing better than jumping into her Mini, speeding along the motorway, blasting Bruce Springsteen.
Other days, she'd insist that she no longer listened to rock, it was un-Christian. Gospel music was all she played. Her favourite book was the Bible, she'd say. She read it every day "for correction and direction".
Next minute, she'd enthuse about her favourite film, Gone With The Wind, and its tempestuous heroine. "Scarlett O'Hara is wonderful. What a spirit!" she'd declare. At home, Iris's ornaments reflected her complex personality. Marie Antoinette sat inches from the Last Supper.
In her authorised biography, Iris said that as a child she'd loved hearing stories of Jesus: "I knew I was supposed to be a good girl. I did try for a few days, then I was as bad as ever!"
The grown-up Iris faced similar turmoil. "I would love to have Moses, Jacob and Christ around a [dinner] table to hear what they have to say," she announced, predicting she'd meet them in the next world.
Yet in this world, she was enjoying less spiritual pleasures with Kirk McCambley, her handsome 19-year-old lover. He was young enough to be her grandson. Iris's eldest son, Jonathan, is in his late 30s.
From a feminist perspective, perhaps Iris's affair is to be savoured. How many aging men enjoy young sexy girlfriends without anyone batting an eyelid? And, as a woman of pensionable age, her libido is surely to be celebrated.
Iris never did anything without passion. I always found her a warm, kind, emotional woman. But there is something highly disturbing about an affair with a boy she'd known from the age of nine.
She was highly manipulative, too. She secured the money for her lover from two property developers, but demanded Kirk give her a £5,000 cut. The Robinsons earn almost £600,000 a year from politics.
When the affair ended, Iris seems to have been petty and vindictive. She ordered Kirk to repay the £45,000. She set a deadline. The image of Iris as Peter's meek, subdued wife is nonsense. Here was a woman mercilessly wielding her authority.
And this wasn't Iris's first affair, a one-off mistake as a result of mental instability. She allegedly had an affair with Kirk's father, Billy. There was reportedly another affair in the 1980s with a DUP member.
After Peter Robinson led a loyalist invasion into Clontibret, Co Monaghan, the RUC withdrew security from his east Belfast home. Off-duty security force members provided the Robinsons with protection. The DUP member is alleged to have regularly visited Iris when Peter wasn't at home and had numerous sexual encounters. Iris once visited the Rev Ian Paisley and said she wanted to leave Peter. Paisley advised her to try to make the marriage work for the sake of their children.
The Robinsons' three children - Jonathan, Gareth and Rebekah - are all well-mannered, well-adjusted individuals of whom any parent would be proud. Iris loves them immensely and they must be shattered by what has transpired.
In spite of her visit to Paisley, Iris publicly presented hers as the perfect marriage. Everything about Peter was 'brilliant'. Anytime we chatted, she'd tell of some expensive gift he'd just bought her.
But the impression lingered of a lonely woman whose husband led a very separate life. She'd complain that he was rarely at home - and when he was there, he was locked in the study.
Iris was a generous host. When my daughter Alanna was born, she invited us for lunch. She had bought her a hand-painted tea-set. "From Auntie Iris", the card inside read. Iris was a woman's woman. She'd curl her legs up on a chair, mug of coffee in hand, and spill her heart.
She was brutally honest in discussing her depression following her health problems and hysterectomy at 34. Yet she could be neurotic.
She had odd ideas. She told me the Robinsons could rarely eat out: "We have to be very careful. About 10 years ago, we had a meal in a restaurant on the outskirts of Belfast which had a very nationalist staff. Peter ordered steak. They put rat poison in it. He suffered bleeding and was extremely sick."
She was obsessed with clothes. She noted that Sylvia Hermon MP, who once was "so dull wearing grey and black is now copying my style".
Peter Robinson was faithful to Iris, but she could be jealous for no reason. DUP colleagues teased her about one attractive female civil-servant who worked with Peter at Stormont. Iris climbed the walls with envy.
Yet within the DUP, she strongly encouraged other women. Iris's Strangford constituency work was first-class. "I fight for my constituents like my life depended on it," she said. On the campaign trail, she was magnificent. While Peter didn't do small talk, Iris was truly a people person.
The Robinsons' home - a huge villa in east Belfast - is Iris's pride and joy. The opulence is overpowering. Curtains of wine and gold silk rising into a central coronet, towering Chinese vases, hundreds of priceless antiques, and chandeliers in every room. "I think I was born in another era," Iris said as she gave me a tour.
Each room was themed. The dining room was oriental, the sitting room was old English, the bathroom was Italian, and one bedroom was French. Iris designed them all herself. She hired an artist to paint frescoes - a Tuscan landscape in the bathroom, an African one in the porch.
A massive four-poster Gothic bed with heart-shaped cushions dominated the Robinsons' bedroom. Iris had her own dressing room. Black lacy underwear was laid out for a function she was attending later. She opened her 'bra drawers' to reveal row upon row of sexy lingerie. "Peter has over 1,000 ties and I have as many bras," she said.
Her breath-taking hypocrisy has been exposed - denouncing homosexuality while having extra-marital affairs. The Robinsons' moral pontifications and flaunting of their wealth, have irritated many over the years. On the surface, they had it all - the flash home, the holidays in Dubai and Florida, the dream life. But compare them to Ian and Eileen Paisley. One is a marriage of style; the other of substance.
After all these decades, the mutual affection and passion between the Paisleys is evident. He calls her 'the Boss' and is never away from home without phoning to say goodnight.
In the DUP, the Robinsons cornered the glitz and glamour. The Paisleys had the real love-affair.