Kikaijikake no Merdina

Meldina hates humans, and wants nothing to do with them. Since her parents' deaths, she has desired to live surrounded by machines, and everyone in town thinks she's a weirdo. One day, she meets a big machine that she names Machina and treats it as a friend. Her meeting Machina, as well as meeting a potential friend in a girl named Alisa, kicks off a series of events that bring to light dangerous secrets about herself and about her parents' deaths.

(Source: MangaHelpers)