This woman is Mio. She gave birth to a uminaoshi. A uminaoshi is a person who was close to death. When this person is brought to a certain place in the ocean and allowed to die there, they can be reduced to their embryonic state. They can then be reborn if a woman eats the embryo that is plucked from the ocean during a full moon.

In this case, Mio has given birth to her the uminaoshi of her mother Mana. She calls her daughter Isana. Isana is growing up to be like her mother and Mio finds it very disturbing. In this scene, she is standing in the rain and telling herself to be strong for the sake of her daughter as well as herself.