Exercise is the best medicine for stress!

Selena Gomez worked up quite the sweat at pilates class yesterday, but she was still wearing her "Sinners" sweatshirt on the way out. How was she not roasting?!

The "Come & Get" songstress has been putting on a brave face amidst all the romance drama with Justin Bieber, but behind the scenes, her close friends and loved ones are concerned that the situation is taking its toll.

"Selena is a mess. She went from being on top of the world to dealing with nonstop relationship drama. She feels so demoralized and alone. She felt she couldn’t go on seeing Justin if she wanted a relationship with her mom. [Selena] feels a lot of resentment toward Mandy about the decision she made, and they’re barely speaking. So she’s essentially lost the two main relationships in her life, which could be a recipe for disaster," a source dished to OK! magazine.

"[Selena] needs a strong support system around her… there’s too much drama in her life right now. There’s a growing feeling among friends that she should be back in rehab working on herself, before something bad happens," the source added.

At least SG can lean on her gal pal's during this turbulent time!