Unease while the tour was a roaring success, Linda was dogged by a sense of unease about her co-star from the very start.
A FLASH of steel lights up Linda Martin's brown eyes and she shifts restlessly in her seat at the mention of former pal and stage mate Twink.
Until now, the former Eurovision winner has been a bubbling cauldron of enthusiasm, chatting animatedly about everything from Jedward to her recent stint in Menopause: The Musical. Yet, perched in a chair in the Westbury Hotel, her face clouds as she recalls the incident that shocked her to the core last May.
"The friendship is over," she declares firmly.
Not altogether convincingly, she adds: "I'm over it, of course I am. Certainly on a professional level I'm over it.
"I didn't get over it overnight and I don't think I'll be able to forget it because the hurt was tremendous, because you're working 24/7 with these people and you're on tour."
Earlier this year, Linda and Twink played alongside one another in Menopause: The Musical, a production which had busloads of mature women travelling to venues to have a comforting sisterhood giggle about "the change".
While the tour was a roaring success, Linda was dogged by a sense of unease about her co-star from the very start.
Sweeping dark brown strands away from her subtly made-up face, she recalls: "I don't know what I did wrong. I just knew from very early on in the tour that there was a little rumble happening. I knew that but I tend to walk away."
Yet, there was nowhere to walk away on the tour's last weekend, at the Harlequin Hotel in Castlebar. Heading to bed at around 1am, Linda opened her window and heard the voices of her co-stars floating out from the room next door.
"All of a sudden I could hear: 'that Linda Martin conspires...' and suddenly "I went from being Linda Martin to a word that begins with C.
"She hated my voice, she's always hated my voice, she was doing the northern accent. She said I wasn't fit to be on that tour. It went on. She said I had deep-rooted emotional problems, which I hadn't. This tirade went on. I was shell-shocked."
Linda recounts the story in matter-of-fact terms. Yet it's hard to disguise the vulnerability that emerges.
"I was sitting there like a zombie and I knew there was nobody I could ring at that hour of the morning. So I sat there like an eejit and it went on and on and on. Eventually I phoned home at a reasonable hour and I was crying by that stage."
That might have been it, but for Linda's decision to challenge Twink the following evening.
"We were in the dressing room and I said to the girls, 'did you have a nice night?' and they said: 'well it was all right, how about you?'
"And I said to them that I'd had a very interesting night. I still remember the words. I said: 'I was in the room next to you guys. My window was open, so was yours and I heard every syllable you said about me'. You could have sliced the atmosphere in that room."
A cackle of wry amusement escapes as she adds: "At the end of the night, she played a request for me from the stage, saying: 'This is a request for Linda who has just gone through a personal trauma today'. And it was her that caused it!
"The sound engineer drove me home that night and that was the final night thank God."
Four months on, there's clearly no love lost. "My opinion of her hasn't changed in that I think she's an incredibly talented actress, comedienne, but the friendship is over," she says.
Just in case cynics have dismissed it all as a publicity stunt, Linda is quick to set the record straight. Yet she insists she's not bothered about the seemingly endless column inches generated by the biggest showbiz spat of the year.
But other celebrities are close to her heart. "I wouldn't hear a bad word against him," she says of Louis Walsh. Just as with Twink, her friendship with him goes back to the 1970s when both were struggling to make their way.
And it was to Louis she turned several years ago. "Luck is with you sometimes and if you're not careful, Lady Luck deserts you and you hit rock bottom.
"And there was one time that I did hit rock bottom in a big way. I landed at Louis's door, I'd nowhere to go and he said 'there's the spare room, go on'.
"I moved in. I'm a very loyal friend and I don't forget things like that. Yes okay, we were friends but at the same time we were still working together. And I just lived there until I got back on my feet again.
"I think it's somebody with a big heart who would do that. The man underneath the bravado is a very kind-hearted, down-to-earth human being. I just think he's an incredible person."
Three years ago, Louis proved his loyalty a second time when Linda was dropped as a judge on RTE's You're A Star. He spoke out in favour of his long-time friend and went on the Gerry Ryan Show to kickstart a petition to re-instate her.
It wasn't enough. But despite the snub, she clearly didn't waste too much time obsessing over it. "You don't be in showbiz the length of time I'm in it and not have changes. If showbusiness didn't change, Jesus Christ, it would bore the a*** off you. So I didn't have an axe to grind."
Nor did she sever ties with Shinawil, the You're A Star production company. "I said to people, 'do you honestly expect me overnight not to be friends with these people and their families? I've been in their houses, I know their children'."
Her graciousness paid off, as it was Shinawil's Larry Bass who later recommended her for the role in Menopause: The Musical.
"I got three years work out of that," she exclaims gleefully.
This is the personality trait that makes Linda Martin so likeable. In fact, it's difficult not to warm to her no-nonsense manner where no topic is off-limits and nothing is exaggerated.
And she's refreshingly honest about everything, from her age ("I'm 58 and my birthday is in March. Don't believe what you read on Wikipedia") to her regrets ("I should have branched out solo earlier").
And she's passed on her wisdom, mentoring Jedward, at the behest of Louis Walsh, before they entered the X-Factor boot camp. "They're lovely people, well reared with a mother and father to die for. Showbiz is about entertainment. I know fabulous singers who can't get a gig because they can do nothing else except sing. But these guys have tapped into that childish energy level that kids appreciate because they realise that what you see is what you get.
"I brought them into the Olympia for a crash course and we brought in a sound engineer, put the lights up, microphones and everything they'd have on stage.
"If you point the microphone the wrong way you get feedback, but what's feedback? You have to experience it to know what it is. And knowing Louis Walsh so well, the top of the list was "please" and "thank you".
In the coming months, she'll get to see the fruits of her labour when she stars alongside the twins in the Christmas panto Cinderella.
"I'm the fairy godmother and Jedward are my fairy godsons," she giggles.
In the meantime, before rehearsals get underway, she'll be busy tracking down celebs to pose for photographs for her animal charity work.
"I got a call this morning. It was one of my neighbours to say there was a dog stuck down at the end of the lane. I was still in my pyjamas and I went down and sure enough a little tiny thing was caught in the brambles!"