Ancillary Justice by Ann Leckie

On a remote, icy planet, the soldier known as Breq is drawing closer to completing her quest. 

Breq is both more than she seems and less than she was. Years ago, she was the Justice of Toren - a colossal starship and an artificial intelligence controlling thousands of soldiers in the service of the Radch, the empire that conquered the galaxy.

An act of treachery has ripped it all away, leaving her with only one fragile human boy. But that might just be enough to take revenge against those who destroyed her.  

A book by author Adrian Tchaikovsky.