The former Moesha star was six months pregnant with Federline's second child when she learnt of his affair with Spears.
Jackson admitted she had urged dancer Federline to go to Los Angeles to find work after she became fed up of supporting him.
'Ironically, I was the one who said, 'Hey dude, you need to get a job. The thing where I'm the only one with an income is not going to work,' Femalefirst quoted her as telling Star magazine.
Federline moved to Los Angeles for auditions in 2004, met Spears and eventually married her in September the same year.
'I was hurt really, really bad. It was the stupidest thing to think that Kevin would leave me when I'm six months pregnant with his baby. I just couldn't believe it,' Jackson added.
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