The 37-year-old and Graham split in 2012, just six months after getting married – having been together for 11 years.
Now former Hear'Say singer Myleene, who shares two daughters with Graham, has insisted she will never let anybody hurt her like that again.
Speaking to The Sun, she said: "No one will ever put me through that again, so help me God."
Myleene insists it was her daughters Ava and Hero who got her through the heartbreak.
She continued: "I couldn't wallow in it and sob. I said to my mum and dad, 'I'm broken, but I will not sink'.
"I just had to keep going, because my girls would be up every morning asking me to make their breakfast or fetch their recorders. My girls saved me. It's taken a long time to get here, and a lot of soul searching."
It comes after Myleene vowed never to marry again – because she wants to protect her fortune.
Classic FM presenter Myleene was thought to be worth £11 million at the time of her split from Graham, and she suggested she lost out to him.
Discussing their decision not to have a prenup, Myleene said: "That was a stupid as it gets. One of my girlfriends said later, 'You married a former drug dealer who wouldn't sign a prenup. What were you thinking?'
"If I'd decided to gamble with my money, I could take that, but someone taking it… No."