He loves her ... he loves her not -- TMZ has learned, Justin Bieber and Selena Gomez have broken up multiple times in the last few months.
Sources in a position to know tell us, Biebs and Selena most recently ended things last week -- but have since decided to give their relationship another try ... kinda.
We're told Justin and Selena's current situation is tenuous ... they're not "solid" ... they're just figuring things out.
They've been dating for roughly a year and a half.
Is there trouble in paradise for Justin Bieber and Selena Gomez?
A source tells PEOPLE that Gomez, 19, "was crying about Justin and was upset" during Ashley Tisdale's birthday bash last week.
But multiple photos from the fete show the "Love You Like a Love Song" singer all smiles, appearing to be in upbeat spirits. She was even photographed being twirled around by a man identified as Bieber's close pal Alfredo Flores.
TMZ reported Monday that the young lovebirds broke up last week, but have since gotten back together.
The couple faced split rumors last August, but quickly proved they were still an item when they sat next to each other smiling at the Teen Choice Awards.
After publicly confirming their romance by smooching during a press conference in May 2011, their relationship has included over-the-top date nights, a helicopter trip and family bonding.
Just a week ago, Gomez, 19, and Bieber, 18, were photographed wearing coordinating outfits at the Katy Perry: Part of Me 3D premiere.
Neither half of the Twitter-happy pair has addressed the breakup reports.