Even though Demi Lovato likes to look like she's got everything under control in her life, fans can't help but wonder if there's something going on behind closed doors with the singer. After the chart topper quit Instagram and Twitter and then rejoined the social media networks again, sources are saying that friends are worried about her "erratic" and "troubling" behavior.

Lovato is known for her outspoken and controversial remarks on Twitter (along with her spats with other celebrities), but for some reason decided that she can't quit the micro-blogging site for more than 24 hours. Yet, one tipster says the reason why she's been acting so erratic lately is simply because she can't get over her recent break up from long-term boyfriend, Wilmer Valderrama.

"She seems to have lost it since she broke up with her boyfriend," one source told Naughty Gossip on Wednesday. "Her behavior is very strange and friends are worried. She has been open about her past struggles and everyone is very worried for her."

Lovato originally took to Twitter on Monday to say goodbye to the Twitterverse after apparently starting and uproar with a Mariah Carey versus Ariana Grande meme.

She then wrote on Tuesday, "F--- this.. I'm back b----es. And I'm coming back more honest than ever."

So far Lovato herself has not made any comments about the rumors.