Aguilera filed for divorce in October, just days after she and Bratman announced they had separated. It takes six months in California for a divorce to become official.
They have a 3-year-old son and have said he remains their top priority.
Aguilera performed at Sunday's Grammy Awards in a tribute medley to singer Aretha Franklin, and also sang the national anthem at this year's Super Bowl. The performances weren't without glitches -- she botched a line in the national anthem and took a spill on the Grammys stage.