But now Jane's husband has revealed the encounter between Kieran and his wife was 'more like a drunken kiss' than a 7 month affair, describing the furore as a 'storm in a teacup'.
'A lot of this drama has been a storm in a teacup and there's a lot of misunderstandings to sort out.'
Katie took to her Twitter on Wednesday to announce her shock divorce from Kieran, who she has been married to for just over a year.
And after venting her anger against the pair, calling pal of 20 years Jane a 'wh*re home wrecker sl**' and Kieran a 'disgusting human being,' Katie stormed round to Jane's house for a dramatic confrontation.
Arriving at the property in West Sussex at around 3pm, Katie, Kieran, Jane and her husband had a tearful conversation about the romance.
But now Jane's businessman husband Derrick Pountney has played down the affair, saying:
'We are good friends of Kieran and Katie and have been good friends of Katie for 20 years.'
'All four of us are good friends, things between Jane and Kieran just went a bit far'
'A lot of this drama has been a storm in a teacup and there's a lot of misunderstandings to sort out.'
The husband added: 'Jane and Katie have had a good old chat here this afternoon.'
'Will she and Kieran break up, or could they get back together? I don't know.'
'The 'affair' has not really happened how its been portrayed. I've known about it for about four weeks myself. All four of us are good friends, things between Jane and Kieran just went a bit far.'
Derrick admitted he was irked that Katie had broadcast the news on Twitter, as she'd turned a drunken kiss into a full on affair for the world to see.
He also added that he was the one who brought Kieran to the house yesterday afternoon so they could all talk things out, adding 'there were tears shed here today, all sorts went on', but that the foursome are on speaking terms again.
Katie released an official statement on her website late Wednesday afternoon. It read:
'I appreciate most people will have seen my tweets on the subject of my marriage to Kieran. I make no apologies for them though it will be appreciated that, sending them immediately after Kieran confirmed to me what he had been doing for the last 7 months, those tweets were a sign of my heart breaking. That he was doing it with a close friend of nearly 20 years is hard to understand.'
'This statement however is from my head, not my heart. I am appalled that someone I loved, trusted and believed in has behaved in this way. If he had so little respect for our relationship I would have hoped he would have thought about our child or the one that we have on the way. That he did not means he will no longer be part of my life. I will do all I can to ensure he maintains a relationship with his children should he want that.'
'I am so grateful for the love of my children and family at this time.'
A close friend of Katie's revealed that the star had suspected Kieran was having an affair for weeks.
'Katie was concerned the spark seemed to have gone and had her suspicions something was going on. But when she confronted Kieran he always told her that she was mad or crazy.'
The pal also added that Kieran had been unhappy about how Katie wasn't making an effort, and that she would be rude and coarse to him.
She added: 'There's no going back. This is divorce as far as she's concerned. She's absolutely determined he is not going to get any of her money either' added the friend.