I remember when I read that in LN, or I guess it was in Web version, still that is some absolutely messed up childhood, this is how most brutal villains are usually born, someone who just wants to rule the world won't compare to someone who wants whole world burned, very satisfying fate for her family pure karma with no sugarcoating or mercy, on the other note, that world is sure brutal, there is so many dangers that grinding strength like cursed with life always on edge feels more safe and serene than knowing that one day you can encounter monster, bandit, thief, assassin, mad mage, demons, or just particularly souless humans and each and every one can kill you if you are just living peacefully, brrrr