The 23-year-old star reportedly spent all day at the country singer's house in Beverly Hills before returning home, reported Us magazine.
Pattinson on the other hand has moved out of Stewart's house following the break up after Stewart's alleged fling with director Rupert Sanders.
"She tried, they both tried. They're both good people. It was just not the right thing for either of them right now.
"All this stuff came up. A lot of issues came up. (They argued) about the cheating, about how selfish she always is, about how moody she always is." a source said.