Amanda Bynes took to Twitter on Wednesday for the first time in months to share a beaming photo of herself and her friend, makeup artist Troy Jensen, along with a cheerful holiday message for her fans.

"Me and my bestie @itstroyjensen! Happy Holidays!" Bynes tweeted alongside the cheerful photo.

WATCH: Amanda Bynes Makes Rare Appearance in Revealing Dress at Hollywood Hotspot

In the pic, Bynes -- rocking long, bright blonde locks and a sexy black lace top under a leather jacket -- is all smiles she she poses with her "bestie."

A source tells ET that Bynes was spotted shopping by herself at the H&M inside the Westfield Fashion Square mall in Sherman Oaks, California on Wednesday night, wearing a white coat and black pants. Bynes later was seen eating dinner alone at a Chinese restaurant in the mall's food court.

WATCH: Amanda Bynes Shows Off Platinum Blonde Hair in First Tweet in Months

"She looked very somber, and lonely," said the source, adding that the outfit Bynes wore in her recent tweet was the same she wore while leaving a nightclub in West Hollywood on Dec. 11.

Bynes' cheerful pic with Jensen is similar to the photo she posted in her previous tweet back in August when she shared a pic of herself and fashion designer Michael Costello.

WATCH: Amanda Bynes Out of Psychiatric Facility, Back to Tweeting Bizarre Messages

The 29-year-old "Easy A" actress made a rare public appearance at the beginning of the month when she was spotted rocking a cleavage-baring, zip-up white dress at Craig's restaurant in West Hollywood.