After the dissolution of the First United Front, she joined the Chinese Communist Party (CCP), becoming a leader of its women's branch in Pi.

[5] The book Chinese Women Heroes (中华女英烈) indicates that Xu was pregnant at the time and withstood torture while held at Suzhou Prison.

The couple moved to Xi'an, where Song became the editor-in-chief of the Northwest Cultural Daily,[5] Meanwhile, Xu withdrew from the public eye,[6] even as she also advanced efforts to challenge the encroaching Imperial Japanese Army.

[8] Song Qiyun was rarely home, and after two months without communication from him, in November 1941 Xu Linxia took her eight-month old son to Chongqing after hearing that he was awaiting them in the city.

[9] Xu and Song Zhenzhong were initially held in Chongqing, but by March 1943 they had been transferred to the Xifeng concentration camp.

[9] Xu continued her sewing; in his memoirs, Han Zidong [zh] recalled that she had prepared bags and clothes for him that he used during his successful escape.

In an interview with the China News Service, Xu's eldest son Song Zhenhua recalled that her writing was ragged, and said that he later learned that she had gone blind and experienced mobility issues.

[5] Her family learned of their deaths two months later, after the Central Committee of the CCP published a letter of condolence in local newspapers.

[9][10] The General Yang Hucheng Cemetery, where the family are interred, is regularly visited by schoolchildren who clean the tombs; it has received a tourist attraction rating of 3A.