Robert Pattinson and Kristen Stewart
05/18/2013 at 05:00 PM EDT
fans may want to sit down for this one.
As rumors of relationship trouble continue to swirl, a source tells PEOPLE that Robert Pattinson
and Kristen Stewart
have called it quits after more than three years of dating
. Reps for the two could not be reached.
But the source says it would not be surprising if the on-and-off-again pair got back together again.
The news follows online reports that Pattinson ditched out on his 27th birthday plans arranged by Stewart.
Prior to his birthday, the pair appeared to be on and going strong: They were seen in New York together after the Met Gala – and then flew back to Los Angeles together on May 8. They also recently celebrated Stewart's 23rd birthday together
and held hands at Coachella
– despite the actress's cheating scandal
with her married Snow White and the Huntsman
director Rupert Sanders last July.
Following the ordeal – which included a public apology
from Stewart to Pattinson – the duo reunited
less than two months later and appeared to be back to normal.
With the exception of some paparazzi kissing shots
and Stewart's admission of her fling, after which she openly professed her love for Pattinson, the two never publicly addressed their romance.
Stewart was known for playing coy about her relationship in interviews, most recently telling Today
's Savannah Guthrie she likes to "keep 'em guessing" about her love life.