"They had another huge fight," says a source, "and Selena won't forgive him."
The reason, according to the New York Post's Cindy Adams, has to do with Bieber's purported parting words: "Don't let the door hit you on the way out," which is right up there with "I'm rubber, you're glue" on the list of clichéd exit lines.
Gomez, 20, reportedly made a beeline back to Los Angeles on Dec. 30.
Bieber, 18, is said to be "really down about the breakup," with the mag speculating that recent pics of him allegedly smoking pot are his way of "acting out" over the split.
A Selena confidant believes Justin is a "bad influence," and insists she's "done with him."
As we await Swift and Gomez's duet on a breakup power anthem, click on for more photos of Haylor and Jelena, the way they were ...