Source: Custody Loss May Be "Wake-Up Call" for Britney

Britney Spears may not be a bad mother, but she's a pretty sucky direction follower.

A source close to the beleaguered pop star tells E! Online that her ongoing refusal to listen to advice or instructions—be it from her parents, publicists, managers, assistants or attorneys—is what has cost Spears so dearly in recent months, culminating Monday with the loss of primary custody of sons Sean Preston and Jayden James.

"So, when a judge now comes in and tells her what to do, she just isn't going to do it," the source said. "It's part of a long pattern of behavior from her. She's become a spoiled brat, to put it mildly."

The source said Spears felt she didn't need parenting classes, so she blew off the request. And she just didn't want to "deal with" the bother of getting a new license—or the humiliation of drug testing.

"And when Brit doesn't want to do something, she just doesn't," our source said. "Even when her kids are at stake. That's the saddest part of all."

Spears' attorney echoed those remarks.

Speaking to People, Sorrell Trope, the latest attorney to make his way through the revolving door that is Spears' legal representation, Los Angeles Superior Court Commissioner Scott Gordon granted custody to Kevin Federline because "we weren't able to prove compliance with what the judge ordered."

Spears failed to take a random drug and alcohol test, one of the stipulations of her maintaining joint custody. "There's no evidence that she actually failed a drug test," Trope said, but added that judges consider missed tests the same as failed tests.

The "Toxic" singer was also unable to provide the court with proof of a California driver's license by 10 a.m. Monday, something both she and Federline were required to do.

An Aug. 6 fender-bender Spears was involved in resulted not only in two misdemeanor charges against her but also in the revelation that Spears was not licensed in the state of California, despite it having been her primary address for the better part of a decade.

Spears not only failed to submit to drug testing, she also neglected to meet with a drug counselor, enroll in parenting classes or even so much as sign the judge's initial order. Meaning she may not have actively done anything wrong, but she also did nothing right.

"That's another example of she does what she wants, but she can't thumb her nose at the judge, at the court," Gloria Allred, the attorney who repped the singer's former bodyguard Tony Barretto, told E! News anchor Ryan Seacrest on his morning radio show Tuesday. "[Gordon] is going to make her accountable, and one of the ways she's being made accountable is she's not going to have her children. She needs to get help if she wants them back.

"And this was a foreseeable consequence of her not doing what the court told her to do." 

While there's no official word on whether the 25-year-old will make good on the judge's order to undergo drug and alcohol testing, Spears is already working on her to-do list.

On Monday afternoon, shortly after Gordon issued his ruling and Spears handed off her sons to Federline at a local Carl's Jr., she went to the Department of Motor Vehicles, where she took a written test as part of an application for a license. That is, after a pit stop at a local shopping mall.

A source close to Federline told E! News that the custody hand-off took place Monday, rather than Wednesday, as that was Federline's regularly scheduled custodial time to be with his kids. While he would ordinarily hand the children back to Spears tomorrow as part of their initial 50/50 split, he will instead simply keep them in his custody until the court rules otherwise.

Meanwhile, Spears' parents are cheering the judge's decision.

"Not because they want to punish Britney, but because they are hoping this will be the wake-up call she needs to get her life in order," another Spears family friend tells E! Online.

"So far, nothing else has worked. Not advice from her relatives, business handlers, legal representatives. No one can get through to her these days. Maybe losing her babies will finally do the trick."

Allred seconded the sentiment. 

"We're hoping this change of custody will give her the strong incentive that she needs to get help so that she can one day be the responsible parent the children deserve to have," the attorney said. "The court's really given her a chance. The court really gave her a second chance."

According to Allred, how Spears chooses to use that second chance is entirely up to her.

"If she doesn't have the children, if she wants to at least have visitation, she's going to take control of her life and get some help. If she doesn't want to have anything to do with the children, then nobody's going to be able to help her...She does seem to be spiraling downward and that is a concern. A lot of people feel very sympathetically toward Britney, you know I do. But she has two young children, she has to really understand what her responsibilities are."

Another custody hearing is set for Wednesday afternoon.

For now, Spears is trying to ride out her latest rough patch in luxury. She is holed up at the Peninsula Hotel in Beverly Hills, where she was spotted arriving Monday night with several suitcases—and several members of the paparazzi—in tow.

Beverly Hills police have even confirmed that one of the hotel's security guards was assaulted by a paparazzo who was trying to get a money shot of Spears on hotel grounds. The extent of the guard's injuries is not known, but he was transported to a hospital following the incident. No arrests have been made, but an investigation is currently underway.