Britney Spears was reportedly lost in her own world during her relationship with Jason Trawick.
The 31-year-old pop star and the 41-year-old talent agent ended their engagement last week.
Trawick has moved out of their shared residence and no longer acts as one of Spears's legal conservators.
It is claimed that spears wasn't mentally grounded enough to be cognisant of the tension between them.
"He had been planning to break up with her for months," a source told Us Weekly magazine.
"Everyone knew Jason was leaving her but Britney. She's in la-la land."
Speculation has been rife that Spears' minders were concerned about her mental health.
They didn't want the singer, who remains the subject of a conservatorship order following her 2007 meltdown in which she shaved her head bald, to have another mental breakdown.
"Everyone is trying their best to keep grounded, but they're scared it could happen again," a source told In Touch magazine this month.
"She was so different, strange new bangs. She just didn't seem pulled together."
The star's father is now her primary overseer.
- Cover Media