Brook asked the rugby star to leave her house last weekend after an explosive row, reported Sun online.
The 25-year-old sportsman, who rekindled his romance with Brook, 33, earlier this year, has reportedly been sending dirty texts and pictures to women for months, even as his girlfriend nursed him back to health when he was hit by a bus in March.
The 'Piranha 3D' actress shared pictures of the pair on a romantic holiday to Greece last week, but has now deleted all photos from her Instagram account.
The brunette's rival, Katie Price, who briefly dated Cipriani in 2011, recently said the rugby hunk would be unfaithful to Brook and claimed he was still messaging her.