LeAnn Rimes has voluntarily checked into an in-patient treatment facility for anxiety and stress, a source confirmed to Us Weekly Thursday.
Reportedly entering the undisclosed facility on Wednesday -- the day after her 30th birthday -- Eddie Cibrian's wife will seek treatment for 30 days.
"She has a lot of mental anguish," the source explains. "She's incredibly hard on herself . . . She really does have a lot of anxiety."
Prior to checking into treatment, Rimes was feted by her husband of 16 months during a romantic Tuesday night birthday dinner at posh sushi spot Nobu in Malibu, Calif. "They looked really happy and were talking a lot," an onlooker tells Us of the couple, who married in April 2011. "He was really animated and she was beaming." Rimes began celebrating her milestone birthday one week earlier during a beach bash August 21, tweeting several photos from the Don Julio tequila-sponsored party.
Turning 30 led Rimes to reflect fondly on the support system she has in her family and friends. "If there's one thing I know, it's that I'm loved," she tweeted. "Thank you all my family, friends and fans for all the birthday wishes!"
Hard at work on her latest album, Spitfire, Rimes is expected to perform concert dates in September during breaks from treatment.
This article originally appeared on Usmagazine.com: LeAnn Rimes Enters In-Patient Treatment Facility for Anxiety, Stress