Selena Gomez checked into The Meadows rehabilitation center in Arizona for 2 weeks of treatment in January.

The "Come & Get It" singer has reportedly been experiencing a combination of problems including alcohol, marijuana and prescription drugs. A source has told Radar Online that before the actress left for rehab, she had been "partying very hard" and "experimenting with marijuana and prescription drugs, including Xanax and Ambien."

Her decision to enter rehab had been pushed by close friends and family, particularly her parents. Another source has told Radar that "The partying was, at times, wild. They wanted to help her, and they very much encouraged her to go to rehab."

The "Wizards Of Waverly Place" actress had explained after canceling her tour in December that "It has become clear that after many years of putting my work first, I need to spend some time on myself in order to be the best person I can be." Her rep has stated that although Selena had spent time in rehab, it was "not for substance abuse."

However, Gomez had gained excessive exposure to drugs and alcohol during her relationship with her now ex-boyfriend, Justin Bieber, who is currently struggling with legal woes as well as his own drug abuse.

It is highly suspected that Selena's ultimate decision was largely based on Bieber. Sources close to Gomez have told TMZ that "People in Selena's camp went ballistic when they found out she was hanging out with Justin and saw photos of her joyriding with him on Segways. That was the final straw. She checked into rehab immediately after that."

Speculation as to whether the young Hollywood pair had gotten back together arose when Bieber posted a picture of the two together with the caption "Love the way you look at me."

After being spotted together with her troubled ex-boyfriend, the 21-year-old's social media came to a stop until the 20th of January when she posted a photo from the Sundance Film Festival.