Louise Griffiths and Jesse Spencer
09/25/2008 at 04:00 PM EDT
After calling off
their engagement last year, House
costars Jesse Spencer and Jennifer Morrison have moved on – with other celebrities.
On Sunday, Spencer hit an Emmys after-party with British singer-actress Louise Griffiths.
"We met through mutual friends out in L.A. at the Green Door [lounge]," Griffiths said at the Entertainment Tonight
Party sponsored by PEOPLE. Australian Spencer tells PEOPLE that they've been dating for "a couple of months."
Spencer, 29, and Griffiths, 30, also stepped out at an L.A. cocktail party two weeks ago. "He was proudly introducing her around and making sure she was taken care of," says a guest. "They were very happy."
Meanwhile, Morrison has been spotted with Prison Break
actor Amaury Nolasco, who split
with Marc Anthony's ex-wife Dayanara Torres in March after a year of dating.
After the Emmys Sunday night, Morrison, 29, and Nolasco, 37, held hands as they walked to their waiting limo outside the Nokia Theater. They also attended a performance of The Zodiac Show
two weeks ago.
Reporting by SHAYNA ROSE ARNOLD and JENNIFER GARCIA