Miyori no Mori(2007)

Miyori no Mori

After being deserted by her parents, 11-year-old Miyori shuts her heart from the rest of the world and denies any form of human relationships. She was entrusted in the care of her grandmother who lives near a forest. Miyori will take a walk in the forest where she felt a strong sense of loneliness in the forest which seems to have nothing. However, she soon encounters unbelievable things and gradually realizes that the forest is more than what it seems...

(Source: Anime News Network)