"She'll be doing this [going to therapy] periodically as a check-in," the source says. "It's really to stay ahead of anything and to ensure she continues to be healthy, and that's something Justin supports 100 percent."
As ET previously reported, Gomez voluntarily checked herself into a wellness program in upstate New York earlier this year.
"This stint in New York was a tune-up after a somewhat stressful month and now that she's back, she's happy to carry on as she was," the source says, referring to the buzz of awards season, going public with her health and her mother's recent hospitalization as recent stressers.
"Justin was one of the first people she saw when she got out of rehab," the source adds. "He was very supportive of her taking care of her health. In the past, it was always Selena pushing Justin to take care of himself, like by introducing him to Hillsong [Church]. Now, it's his turn to push her to take care of herself."
"They've both matured and have very different priorities. Justin isn't interested in partying and Selena is much more confident, and isn't afraid to put her needs ahead of anyone else's," the source says. "They've done the fame thing for so long, now they just want to work on quality projects and live a low-key life."
For Gomez, that includes a focus on new music.
"She's really proud of her last album, but because of her surgery, she didn't get to promote it the way she would have liked," the source notes. "Next time, she'll be much more hands-on with promotion."
And when it comes to Bieber and Gomez's relationship, the source adds that the pair is "in a good place for now."
"You're not going to see them doing anything super flashy or public, they're just going to go about their life," the source says. "They've been to church groups, they've gone out for dinner and they've spent a lot of time at his place."