Norcross branded the glamour-model-turned-bodybuilder a "fame-obsessed liar" in a Reveal interview and claimed she was "always teasing" him with the promise of intimacy.
Marsh has now taken to Twitter and explained that she had only been going out with the "desperate" ex-TOWIE star for two weeks when he broke up with her.
"It's amazing how nasty someone can turn when you won't have sex with them," she wrote.
"I'd only been seeing Kirk for TWO weeks. He had a tantrum cos I wouldn't put out in 2 weeks. Girls should never feel forced into sex. Never!"
She continued: "A ten year friendship ruined cos I wouldn't have sex. Real men don't pressure women. And they don't sell stories on them either.. #desperate
"Dumped cos I wouldn't immediately have sex, stories sold on me, lies told about me. All this & I thought we were friends #Hurt :-(."
Norcross has posted a response of his own on Twitter, writing: "Get over it! We was never 2gether love! Never talked or thought about it!
"It was nothing! Get over it! Just done the story to tell the truth."
The former couple's relationship was exposed when they tweeted pictures of themselves passionately kissing.