Lindsay Lohan's "destructive behaviour" is reportedly concerning her loved ones.

The troubled actress is trying to get her career back on track following numerous brushes with the law and stints in rehab.

She and her assistant Gavin Doyle, who was arrested for felony of cocaine possession in 2008, were suspects in a jewellery theft case last month when Sam Magid filed a report claiming that $100,000 worth of accessories were stolen from his Hollywood Hills home.

The pair weren't indicted on the Magid case due to lack of evidence but the star, who remains on probation from a previous theft charge, is said to be back to her wild ways.

"Yes, Lindsay is partying again," a source told Star magazine.

"Lindsay is drowning, and there is no one hear her who will help. Everyone she surrounds herself with enables her, doing nothing to stop her destructive behaviour."

Lindsay's close circle worries about the star's choice in company.

"For someone like Lindsay, who's been to rehab four or five times and who supposedly is intent on getting her life together, it's mind-boggling that she would choose as her assistant' someone with their own history of cocaine abuse," a friend told the publication.