PHOENIX -- If you've wondered why you haven't heard much from Selena Gomez in the new year, it's because she was reportedly in rehab.
According to Star Magazine, the 21-year-old singer checked into the Dawn at the Meadows rehabilitation center in Wickenburg, Ariz. on Jan. 5.
"Poor Selena tried to put on a brave face, but it became clear she was struggling," an insider reveals. "In the end, she decided to go for treatment."
Gomez's representative claimed she was seeking treatment for exhaustion, but a Star source said she had been using both marijuana and prescription drugs. Both habits began while dating fellow singer Justin Bieber.
"She finally gave into pressure and started smoking weed with Justin," the source says. "His house was the first place she tried it."
Gomez checked out of the 45-day program after just two weeks, but is still being treated.