It's been nearly a year since Selena Gomez checked herself into rehab, but after recently admitting to InStyle that she was happy she canceled her tour last year — just after ex-boyfriend Justin Bieber canceled his tour — fans are once again wondering why she even went to rehab in the first place.

She told the mag, "I kind of wish numbers didn’t exist sometimes because I feel like I’m 15 some days, and then other days I wake up and I’m 40," she admitted. "It’s so weird, how one year can change everything. Last year I canceled my tour and went away for 90 days, and it was the best thing that I ever could’ve done. I had no phone, nothing, and I was scared. But it was amazing, and I learned a lot."

Back in October, In Touch exclusively learned that the singer — who sought treatment for anxiety and depression — had reached rock bottom before checking herself in. "If anyone knew how bad she was, they’d be in shock," a source told us at the time.

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Sel's downward spiral was the result of her trying to portray a perfect image for her fans — she is the most followed person on Instagram in the world, after all — and while she knew she needed help, her time spent at the Brookhaven Retreat in Seymour, TN wasn't always as "amazing" as she said. Another source told In Touch, "Everyone is worried. Selena keeps saying she feels like hell and wants to leave the facility or go switch to outpatient treatment."

These days, however, Selena — who just celebrated her 25th birthday — is happier and healthier than ever. She and boyfriend The Weeknd are "happy" and she also recently released a new video for her song, "Fetish" with Gucci Mane.

She told InStyle, "I don’t depend on one area of my life to make me happy. It’s really important for me to love and nourish my friends and family and to make sure that I never get influenced by a guy," she added. "I’ve wanted to be in a strong headspace for years, and I really wasn’t. Before, I was so young and easily influenced, and I’d feel insecure. You want someone to add to your life, not to complete you, if that makes sense. I’m lucky because he’s [The Weeknd] more of a best friend than anything else." So sweet! We're happy to hear Selena's back.