The City in the Middle of the Night by Charlie Jane Anders

A dystopic look at the pitfalls of civilization, society, and love. Rules on this planet are strictly enforced so when some young students are caught holding a subversive meeting, one of the girls is run out of the colony at gunpoint and cast out over the wilderness to be eaten by alien creatures. Sophie ends up being saved by the lobster looking crustaceans and befriends them. When she eventually meets up with her friends and other revolutionaries, Sophie tries to convince them that they need to work with the Gelet but they only see how the species can be dominated. Her relationships with Bianca, who she secretly loves, and with Mouth and the others seem to skirt between revolutionary, outlaw and survivor. This is a wild ride of man-eating creatures, thieves, pirates and people desperate to understand their place in this alien world. There is much to fear in the darkness.