The Popes teach that “at the cross Mary sacrificed her maternal rights.” A child receives his flesh and blood from his mother; his life is a continuation of the mother’s life. His joys and sorrows are the joys and sorrows of the mother. To offend the child means to offend the mother. To do harm to the child means to do harm to the mother. To take the child’s life is to take from the mother the meaning of her life.
If this is true for reason (through faith), it is just as true for her will, in hope. The deepest desires of the heart of the Immaculata (the honor, happiness and good of her dearly-beloved Son) are offered up to the Father in the mystery of her compassion in an act of complete trust. If we reflect that our consciousness of life is realized in our deepest desires, then we can understand somewhat that through the sacrifice of these desires Mary experienced the most terrible mystical death: death by the sword that pierced the depths of her soul, reaching unto the division of the soul and the spirit [Hebrews 4:12]. Everything about Mary is slain, offered to her Father in the sacrifice of Jesus Himself. Through Mary all of human nature, along with the most profound and personal things belonging to it, is offered up to the Father for His honor and for the salvation of mankind.
https://fsspx.news/en/news-events/news/mother-sorrows-our-coredemptrix-57245