After spending her week out on the town with girlfriends and close family, the mum of four is clearly revelling in her newly single status.
But Now can reveal that what prompted Kerry to ditch her ring was becoming close to two instructors at two different boot camps, with at least one of those leading to an affair.
Kerry, 29, had her first fling with Royal Navy personal fitness instructor Steve Lockton at a boot camp last July.
When that romance fizzled out, at a second boot camp this January she was accused of chasing married father of three Kevin Green, also a personal fitness instructor. The fallout is still ongoing, with Kevin's wife battling to keep her man.
Kerry and Kevin deny that anything happened, but three separate sources have told Now they're convinced something did - and the pair met up only two weeks ago, even though Kevin's meant to be patching up his marriage.
In a bizarre coincidence, Steve and Kevin are close friends who live in the same block of military flats in Eastney, Portsmouth, and work at a nearby naval base.
Kerry always denied to Mark that anything happened, but Mark, 39, had his suspicions.
In July, after Kerry's first fling, he demanded a divorce saying: 'I can't go to bed with a lard arse any more,' before reconciling.
A friend of both couples tells : 'She doesn't realise the pain she's caused. She's destroyed two relationships, but doesn't seem to give a damn.
'What Kerry wants, Kerry gets. She was pursuing these men with texts and Facebook messages. We wish she'd get on with her own life away from married men. Boot camps should put warning signs up when Kerry visits.'
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