Selena Gomez thanked Demi Lovato for helping her during her time in rehab, which was rumored to be contributed by her lupus disease, leaving many fans wondering if the "Let It Go" singer, who is also a writer, is considering releasing a book about her best friend's struggle.

"I want to thank Demi. Just the fact that we're here at 21 years old, and we've always talked about using our voice to help this generation.," Selena Gomez said during speech at a UNICED awards dinner.

"Sometimes I feel like we're the only ones holding the fort and I'm so thankful for you [inspiring] me every day."

Selena Gomez's friends are concerned about her health and the "Slow Down" singer may need to check in for more rehab, PerezHilton.com reports, leaving many fans wondering if her lupus disease may be getting worse.

"It is not humanly possible to recover from your rock bottom that quickly. We're all concerned for her well-being," a source told the website.

"She's still very fragile and not coping with her problems at all. She's jabbering to herself, and everyone is worried she's about to pull a Britney [Spears] - she's a very troubled young girl, and if she doesn't get it together, the psych ward could be next."

Selena Gomez posted a photo of herself on Twitter and Instagram solemnly laying down on a couch with the caption "Dear Marie," leaving many fans wondering if her reference to the despondent John Mayer song is a sign of possible depression over her lupus disease.

However, the "Slow Down" singer seems to have moved on from Justin Bieber based on her Instagram and Twitter posts-many of the statuses and photos that she has posted feature her spending time with friends and having fun, despite rumors of her being pregnant and having lupus.

Earlier this week, she posted a pic of herself on Instagram wearing a wig while sitting next to a woman with a film-recording camera, leaving many wondering if she may be shooting a film about her rumored struggle with the Lupus disease.

The picture was posted in black and white on Friday.

But Selena Gomez is having a tough time getting over Justin Bieber and finding romance, PerezHilton.com reports.

She also posted a photo of bible verses she read and underlined.