Why was Lady Fatimah (may Allah be pleased with her) named Az-Zahra and Al-Batoul?

Al-Nawawi said that "al-tabattul" (devotion) is abstaining from women and refraining from marriage for the worship of Allah. The root of "al-tabattul" is cutting off. From this, Mary and Fatima were named "al-Batoul" (the Virgin) due to their detachment from the women of their time in religion, virtue, and desire for the afterlife. Ibn Hajar said that Fatima was named "al-Batoul" due to her detachment from husbands other than Ali, or due to her distinction from her peers in beauty and honor.