The 'Toxic' singer and her fiance of over 7 months, Trawick, are having major problems in their relationship due to the pressure of her new judging gig, reported Radar Online.
"Their relationship has been majorly rocky ever since she started filming The X Factor. They are constantly fighting about everything, and it isn't good," a source said.
The source also said that Trawick, who became Spear's co-conservator in April, is less than pleased that he has gone from being a big time Hollywood agent to Spear's full-time babysitter.
"When Jason left his job at William Morris Endeavor in May 2011, it was under the impression that he was going to be managing Britney's career, but that hasn't happened. Now he feels like he is the house husband and errand boy in the relationship, and that isn't what he signed up for," the source added.