As the 1960s progressed, the Singing Nun stopped performing and entered a rigorous religious life in the convent in 1965. In 1967, however, she left the convent to pursue her musical career, though most of her earnings still went to the convent. Nevertheless, she was a one-hit wonder, who gradually faded into obscurity, not least because of her own disdain for fame: her second album, released in 1967, was aptly titled I Am Not a Star. Though she was deeply religious, she was also increasingly critical of the conservatism of the Roman Catholic Church, and she became an advocate of birth control.
Having faded into obscurity, she opened a school for autistic children in Belgium with a close friend, Annie Pescher. By the early 1980s the Belgian government began claiming that she owed back taxes; she claimed that the money was given to the convent and therefore exempt from taxes. In 1985 she and Pescher both committed suicide.