It seems that Justin Bieber still can't get over Selena Gomez as he tried so hard to get her attention by rekindling his relationship with model Yovanna Ventura during his 21^st birthday celebration. However, it appeared his efforts failed since ex-girlfriend Selena Gomez could have cared less who he was hanging out with on his birthday.

Sorry, Justin Bieber! Selena Gomez has already moved on. Though she was uninvited to Bieber's birthday shindig, she posted a provocative thigh-high boots selfie from her bedroom on Sunday morning, The Daily Mail reported. Intentional or not, Selena just knew how to tease her ex-boyfriend as the Instagram post coincided with Bieber's special day.

On March 1, Canadian pop star Justin Bieber celebrated his 21^st birthday on a private island with his pals. According to Hollywood Life, Bieber rented out an entire Caribbean island and kicked off the revelries by popping up a big bottle of champagne as he danced to 50 Cent's "In Da Club" song. He celebrated with Hailey Baldwin, Alfredo Flores, Matthew Espinosa, Ryan Butler, Soundz and old flame Yovanna Ventura.

Though Justin Bieber and 18-year-old Yovanna were not seen together for months, they both appeared super cozy together. So are they hooking up again? What will Selena Gomez say?

Well, a source said that 22-year-old Selena Gomez wasn't surprised or even upset because she was aware that the model held a torch for her ex-beau.

"Selena doesn't really care who Justin hangs out with - and wasn't surprised that Yovanna and Hailey [Baldwin] were at the party," the source shared.

It's quite surprising to hear that Selena Gomez is now unaffected by who Justin Bieber is hanging out with. Perhaps it's because of the rumored new man in her life, DJ Zedd.

"She's moved on with Zedd, an older boyfriend, and is enjoying the most grown-up relationship she's ever been in," an insider explained.

Meanwhile, another close pal, Cody Simpson, also didn't get an invite to Justin Bieber's 21^st birthday party. So Cody and Bieber's ex Selena decided to hang out together over baked goodies.

What do you think of Justin Bieber and Selena Gomez's relationship? Have they finally moved on?