Brüning was born in Berlin. In 1930, she joined the Communist Party of Germany. Before World War II, she was arrested in 1935 for communism-related activities, before being released in 1937. In 1937, she married Joachim Barckhausen, a writer and editor. Their daughter, Christiane, born in 1942, also became a writer. After the German reunification, she became a member of Die Linke (). Brüning turned 100 in November 2010.