In 1857 in an attempt to clarify her vocation she entered the Sisters of the Sacred Heart in Bloemendaal, Netherlands. However, she left the order in March 1863 unable to commit herself to a congregation whose main purpose was education. In further attempts to try her vocation she spent short periods with the Sisters of Perpetual Adoration and the Visitation Sisters. In 1875, in the presence of her spiritual director Dr. von Essen, she made a private vow committing herself to the mis-sions. In part of the former convent in Neuwerk she cared for orphans and gave the opportunity for older ladies to live a common life. However, it remained difficult for her to fully realise her vocation and she continued to search for a missionary community which she could join and put her resources at its disposal.

On 25th April 1882 she answered an advertisement placed by Father Bonaventura Lüthen for the Apostolic Teaching Society. The founder, Father Francis Jordan, visited her on 4th July 1882 and stayed for three days. He made a deep impres-sion on her and on 5th September 1882 she became the first female member of the first degree of the Apostolic Teaching Society. In 1883 Father Jordan estab-lished a group of sisters in Rome but asked Mother Mary to remain in Neuwerk as a sister of the Catholic Teaching Society. However, problems occurred with the sisters in Rome and on 13th October 1885 they were separated from Father Jor-dan; they continue today as the Sisters of the Sorrowful Mother. In 1888 Father Jordan called Mother Mary to Rome. He found a house for the sisters in Tivoli and on 8th December 1888 she and two others received the habit from Father Jordan. On 25th March 1889 she made perpetual vows in the Sisters of the Catho-lic Teaching Society and was appointed superior. In December 1890 three sisters were sent to the first mission of the Society in Assam, India. By the end of 1892 there were about 50 sisters and novices in the house in Tivoli and they were being sent out to many different parts of the world. In 1894 a typhus epidemic broke out in Tivoli and seven sisters died, this finally prompted the move to Rome. Mother Mary of the Apostles was unanimously elected as superior general at the first general chapter of the Sisters of the Divine Saviour in 1905. She died on 25th December 1907 after a short illness. In recognition of her personal virtues, trust in divine providence and commitment to the missions she was beatified on 13th October 1968. Her feast is kept on 5th September.