Model Katie, 36, was left heartbroken when she learned on 7 May that Kieran and Jane had been involved in a sexual relationship for seven months.
Making it even worse was the fact that mother-of-four Katie is currently six months pregnant with Kieran's second child.
While Kieran, 27, initially kept silent about the affair, he has now broken his silence by giving interviews to The Sun, revealing today that he's currently undergoing therapy at a £2,500 per day facility in order to treat compulsive addiction.
Part of that treatment included writing a letter to Jane, which he showed to the newspaper.
In the letter, Kieran writes: "I was never going to leave Katie for you. I am so glad we got caught because now I can get help and I can start a new fresh life with Kate with good people in our life and positive future."
Kieran tells Jane that their affair was nothing but a "dirty, sleazy shag to feed an addiction that I'm ashamed and embarrassed to say I have."
He added to The Sun that therapy had made him realise he has what is known as "compulsive addiction", explaining: "I lie compulsively to get an adrenaline buzz."
Kieran and Katie married in the Bahamas in January 2013 following a whirlwind romance and Christmas proposal. Their first son, Jett, arrived that summer, while their second child will be born later this year.
Since discovering the affair, Katie has kept a low profile - although she did take to Twitter over the weekend to blast Kieran for another interview he'd done describing his sexual encounters with Jane.
Kieran has said his priority now is to win Katie back and that he has "deleted Jane completely" from his life.
Jane, meanwhile, has said she "deeply regrets" the affair.
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Katie Price's ex-boyfriends in pictures:
Copyright: PA Images