Book about a frozen dystopian world

In 2009 I read a book for school, which I'd like to re-read but I cannot remember the title. It was about a boy and a girl in some dystopian world (I think it was told from her and his perspective and that they weren't together all the time or perhaps at all). The world was icecold or frozen too, (they perhaps even burned things to feel) and I remember there was also something about a motorcycle gang (with horns on their helmets) and a king.