Selena Gomez Checked Into Treatment to Help Her Move Past Justin Bieber Breakup Experience

Substance abuse has "never been an issue," source assures E! News in wake of reveal that the 21-year-old spent two weeks in rehab in January

Add Selena Gomez to the countless others who've needed a little extra help to get by after a tough breakup.

While the 21-year-old's rep previously confirmed that Gomez didn't spend two weeks in treatment last month for any sort of substance abuse issue, now we have a better understanding of why the "Come and Get It" singer did need time to "clear her head."

A source tells E! News that Gomez, who was out of rehab in time to attend the Sundance Film Festival, checked in right after a photo surfaced of her riding Segways with ex-boyfriend Justin Bieber near his home in Calabasas.

"The last straw was seeing them on the Segways," the source says. "She needed to work on her emotional life. She needed to learn tools on how to deal with Justin and letting go of that relationship.

"This is the first time she's ever taken the time to deal with issues, to deal with herself, with a therapist."

An eyewitness in the neighborhood noticed the famous exes riding around and tweeted a pic on Jan. 2. Two days later, Bieber posted a snuggly snapshot of the two on Instagram with the caption, "Love the way you look at me."

Gomez is, indeed, looking at him quite adoringly. The following day, Jan. 5, she checked into treatment at Dawn at the Meadows in Arizona.

The insider says that her continuing interaction with Bieber was causing a strain in her relationship with her understandably concerned family and friends. Gomez and Bieber first broke up in November 2012. They later reconciled, but by May 2013 Gomez was once again confirming her single status.

As of now, "everything is OK at the moment with her family," the source adds.

Gomez only spent two weeks in the Dawn program, where the recommended stay is usually 45 days, most likely because she was not battling the type of issues that would be considered more detrimental to her physical and mental health.

We're told that the Spring Breakers star, who was at Sundance promoting her next film, Rudderless, is currently "reading scripts" but has not attached herself to any new project yet.