Spears, 25, left the Promises Treatment Center in Malibu Thursday night accompanied by a driver and two bodyguards.
Sources tell Us Weekly magazine that Spears has spent a lot of her time in rehab shopping at the online Web site for trendy boutique Intuition.
A source at the store confirms, "She was emailing things that she saw on the site and wanted to buy."
Intuition owner Jaye Hersh adds, "Britney is doing great. She's really happy. She loves the store. She wants to look better and knew that we would take care of her."
The "Toxic" star went to an apartment in Culver City, California, where she met up with her cousin Alli, with whom she has been in close contact since seeking treatment.
The pair emerged after 20 minutes and Spears returned to the car with a shopping bag from Intuition that appeared to be full of clothes.
Spears, who has already left rehab facilities twice during treatment, made sure she was back at Promises by 9 p.m.
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