Bruno Mars, Sting and Fifth Harmony also performed at the award show.
Selena Gomez bared her heart and soul as she accepted an award at the American Music Awards Sunday night, her first public appearance since leaving rehab.
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The 24-year-old pop star put her career on hold three months ago for treatment of anxiety and depression, as well as lupus, and addressed her issues when she won for Favorite Female Pop/Rock Artist.
“I kept it all together enough to where I would never let you down," she said. "But I kept it too much together to where I let myself down. I had to stop, because I had everything and I was absolutely broken inside.
"I'm not trying to get validation, nor do I need it any more. All I can say is I'm so grateful that I have the opportunity to be able to share what I love every day with people that I love.
She added: “I have to say thank you so much to my fans, because you guys are so damn loyal, and I don't know what I did to deserve you. But if you are broken, you do not have to stay broken. That's one thing you should know about me — I care about people. And this is for you."
Lady Gaga cheered Gomez from the audience and then backstage with a huge hug.
Bruno Mars kicked off the show and Ariana Grande rocked the house before taking home the night's highest honor — Artist of the Year.
Girl group Fifth Harmony performed in a Mad Max-esque setting of flaming rubble and ruins.
While the younger generation of stars had fans tuning in, the show was made for all ages as music vets and icons were honored.
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Sting brought down the house as he performed a medley of his classic hits before being honored for his life work.
Prince’s Purple Rain won Best Soundtrack — 30 years after its initial release. The iconic album for the 1984 film became eligible for the award after the "Little Red Corvette" singer's death in April led to a resurgence in sales.
“We'll keep this for you at Paisley Park, his sister, Tyka Nelson said as she accepted the award for her late brother.
Fighting back tears, she added: "Until we see you again, this is for you."
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