We Are the Ghosts

After her estranged brother suddenly dies, a girl embarks on a road trip to rediscover who her brother really was in Vicky Skinner's contemporary YA novel, We Are the Ghosts.
When Ellie's estranged brother, Luke, dies in a car accident, she's not sure whether to be devastated that she lost the person who was once her best friend or enraged, still, that he left without a word a year ago. Now, the only people who seem to understand what she's going through are Luke's best friend and his ex-girlfriend, who she bonds with over their desire to figure out where Luke went when he walked out of their lives.
As she gets closer to them, and closer to Cade, a boy who seems determined to get to know her better, she realizes that she's not the only one with reasons to be angry at Luke. And when Ellie makes a discovery that changes everything, she and her new friends hit the road, hoping that following Luke's trail will bring them answers about the life Luke was living away from them.