The Wanted star was secretly sexting and having phone sex with his former flame, while poor Michelle was completely unaware on his love-rat antics.
Bobbi, 29, said: "Phone sex was natural between us. I could literally get it at the click of a finger. But he would also tell me I was the love of his life and that he would always love me."
She added: "I would often say, "Max, you have a girlfriend and she's gorgeous". He would say, "I know, I know" but then send me another text."
Max, 23, and Bobbi have known each other since 2007 but ended their three-year romance in November 2010.
Within weeks he was dating actress Michelle, 25, but less than three months later he got back in touch with Bobbi.
Bobbi's revelations came just after Michelle dumped Max when he was caught kissing a mystery blonde in a Newcastle nightclub.
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