Britney Spears' Ex-Friend -- Stay Away!

9/28/2010 1:45 PM PDT BY TMZ STAFF
Britney Spears' infamous former friend Sam Lutfi now has a growing list of people he's not allowed to hang out with -- because it now includes the roommate who recently accused him of psychotic behavior.

The restraining order -- filed earlier this month by an aspiring actor/model named Samuel Barth -- just got the thumbs up by a judge during a brief hearing in L.A. County Superior Court.

0928_barth_tmz_v3As we first reported, Barth accused Lutfi of trying to diagnose Barth
with mental problems (just like Lutfi allegedly did to Britney) ... then
allegedly stalked him and members of his family.

Lutfi must now stay 100 yards away from Barth for three years.