Brooke Mueller is in rehab at Cirque Lodge in Utah, X17online can exclusively report.

Charlie Sheen's ex, who was arrested for cocaine possession last December in Aspen, Colorado, has been at the facility, located in Sundance, for several weeks.

Various reports claim Demi Moore is at Cirque Lodge, as well, and while those claims, we stumbled upon the news that Sheen's ex is there.

A source tells X17online exclusively:

"Brooke is in treatment and doing fine. She doesn't seem too stressed or worried about it. You can tell she's been through this before. Honestly, she'll get through it and she knows there's a good chance this won't be her last time in rehab."

Our source adds that Brooke's parents are staying at a cabin near Cirque Lodge with twin sons, Bob and Max ... bringing them to visit their mom regularly. Mueller is expected to stay at the facility through the month.

Tallulah Willis turned 18 yesterday, and Bruce Willis and Demi Moore's youngest daughter celebrated her birthday at her father's new Beverly Hills mansion last night. We snapped Rumer arriving around 8pm, but there was no sign of Demi (or ex-hubby Ashton Kutcher).

A photographer tells X17online exclusively, "A bunch of Tallulah's friends came, along with her sisters and her dad Bruce, but we were waiting and waiting to see if Demi would show up — like hiding in the back of a car or something — and she never did."

Guests at Tallulah's b-day bash enjoyed catering from an organic food company, and while the music got pretty loud, things died down by 11pm. Sounds pretty standard for an 18-year-old's bash, right?

Scandalous!

A trailer of the upcoming flick LOL has just been released, and it features Miley Cyrus in her first sex scene, while Demi Moore, who plays Cyrus' mom, can be seen clutching a box of condoms and a marijuana joint while quizzing her daughter on her wild ways.

The story centers on rebellious 15-year-old stoner Lola, and her tumultuous relationship with her single mom, who comes home to find her daughter had thrown a wild party -- and lost her virginity in the process.

Definitely a far cry from her Hannah Montana days!

LOL is a remake of the 2008 French film of the same name, and it set to be released in June.

Demi Moore has beefed up security at her Beverly Hills home, X17online can report exclusively.

Sources tell X17online that the 49-year-old actress has hired an armed bodyguard to approve of the people entering her residence, and he's been spotted standing at the end of her driveway with a clipboard of names.

It's uncertain whether Demi is seeking treatment outside of her home, but ex-husbands Ashton Kutcher and Bruce Willis were both spotted visiting her $3.1 million pad yesterday, so it appears as though she is spending time there with those closest to her.

Demi was rushed to the hospital last week after smoking a mysterious substance and going into convulsions, and her oldest daughter Rumer was with her at the time of the incident. Bruce and Demi's youngest daughter, Scout, who turns 18 tomorrow, reportedly lives with the Die Hard actor, so it seems as though everyone will be taking turns visiting Demi as she recuperates.

Now that Demi Moore is recovering at home after being hospitalized for alleged drug use, she's getting special visits from the men in her life ... ex Bruce Willis and soon-to-be-ex Ashton Kutcher.

A somber looking Willis was seen arriving at Moore's LA home Wednesday around 11:30am. The Die Hard actor must be concerned about his daughters being exposed to Demi's troubles. It was revealed the former couple's oldest daughter Rumer was present during Demi's partying and eventual convulsions that led to the actress' hospitalization.

After Bruce left, Demi's estranged husband Ashton Kutcher pulled up to her home in his blacked-out Lexus around 4:30pm. He visited for close to two hours, then the Two and a Half Men star left. Kutcher recently returned from working and partying in Brazil.

Demi Moore had her eyes set on daughter Rumer's good friend Zac Efron, according to Us.

Moore, 49, "tracked down" Efron, 24, at a party in Venice. A source tells the mag, "She seemed out of her mind at this party."

Those close to the G.I. Jane actress say she's been mixing pills and Red Bulls. The insider adds:

"She's been really down, and she's surrounding herself with young people to make her feel better."

As for the night of January 16 when the 911 call was made after Demi reportedly went into convulsions, a source tells the mag, "Everyone thought she was going to die."

Moore and Ashton Kutcher split last year after six years of marriage.

Yesterday Demi Moore's 911 call hit the internet, and friends of the 49-year-old actress told dispatchers that she had collapsed after smoking a mysterious substance.

An unidentified female caller revealed that it was "not marijuana," adding that it was "similar to incense." Demi had difficulty speaking, convulsions and a fever, and now doctors are speculating that she may have smoked synthetic cannabis, also known as "K2," "Spice" or "herbal incense."

Dr. John Sharp, MD, a faculty member of Harvard Medical School explained to Us Weekly that the drug is similar to marijuana but "not necessarily safer" and it doesn't show up in most drug screenings. Some medical studies have linked the use of synthetic cannabis to psychosis, heart attacks and convulsions, so Demi's reaction does seem consistent with someone using the drug.

And that (along with nitrous oxide) weren't the only substances Demi was allegedly using. Prior to her trip to the ER, Demi had been drinking excessive amounts of Red Bull energy drinks, and a source told Us that she drank 12 cans in one evening!

Will the real Parker please stand up?

A report from Us Weekly early Friday claimed that Weeds star Mary-Louise Parker was set to replace Demi Moore in the upcoming biopic, Lovelace, but it's actually Sarah Jessica Parker who will step in to fill the role of feminist icon, Gloria Steinem.

Moore was forced to drop out of the film on Tuesday after being admitted to the hospital for "exhaustion," and the Sex and the City hottie has now officially signed on to play Steinem, according to the film's press release.

Lovelace is currently shooting in Los Angeles, and centers on the famous 1970s porn star, Linda Lovelace, played by Amanda Seyfried, who costars alongside James Franco, Sharon Stone, Peter Sarsgaard and Adam Brody.

Demi is currently putting her career on hold to "seek professional assistance to treat her exhaustion and improve her overall health," her rep said in a statement.