Her husband was accidentally killed out shooting, and in her widowhood she determined to embrace the more excellent way, and took a vow not to marry again. She bore her bereavement with resignation to the Will of God, and so far overcame her horror of the gentleman who had fired the shot, that, to shew she attributed no blame to him, she stood godmother to his little boy. She was quite content with few servants and plain cookery and dress, and sold her rich wardrobe for the benefit of charities. She received offers of second marriage which would have been both politic and honourable, but never was induced to accept one of them, and to harden herself in her intention of remaining in her widowhood, she renewed her vow to that effect, and branded on her chest with a hot iron the most holy Name of Jesus Christ. Her love grew tenderer every day, and she had brought to her the starving, the abandoned, the diseased, and those who were afflicted with the most sickening disorders. Them she not only sheltered, comforted, and nursed, but washed, and mended their filthy and ragged garments, and shrank not from putting her mouth to their sores oozing with disgusting matter.
She used the services of St. Francis de Sales as her spiritual adviser, and when she learnt from him what was the will of God, she scrupled not to disregard the wishes of her own father, brother-in-law, and even of her son, whom she left with calm determination, went forth from her home, and founded the holy Institution of the Sisters of the Visitation of St. Mary. She most rigidly kept the rules of this Institute, and loved so well to be poor, that it made her glad to lack even the necessaries of life. She shewed herself a model of Christian lowliness, obedience, and all graces. Having settled in her heart still to go up higher and higher towards the Temple of the Lord, she bound herself by a most difficult vow always to do that which she should understand to be best. It was chiefly through her labour that the holy Institute of the Visitation became spread far and wide, and she stirred up the sisters to godliness and love by her words, by her example, and by writings full of Divine wisdom. She duly received the Sacraments before her death, and then, at Moulins, on the 13th day of December, in the year 1641, departed hence, to be for ever with the Lord. St. Vincent de Paul, who was far distant, in a vision beheld her soul borne to heaven, and St. Francis de Sales coming to meet it. Her body was afterwards taken to Annecy. She was famous for miracles both before and after her death, and Pope Benedict XIV enrolled her among the Blessed, and Pope Clement XIII among the Saints. Pope Clement XIV ordered her Feastday to be kept by the whole Church upon the twenty-first day of August.