“They had been fighting,” one insider tells Us of the couple, who’ve been together for three years, adding that their schedules were at odds.
JustJared, which was first to break the news, notes the split was amicable. Roberts, 24, and Peters, 28, who both starred in Season 3 and 4 of FX’s American Horror Story, started dating in 2012 and got engaged Christmas 2013.
The Scream Queens actress was last spotted out at The Nice Guy in West Hollywood on June 11 without her ring.
Prior to their engagement, the now-exes got into an altercation and Roberts was arrested for domestic violence in July 2013.
"They're a couple of young kids," a source told Us at the time. "Their romance is pretty extreme. They just behave in a way that's very passionate."