It's Only Temporary (A Tale of the End of the World)
by Eric Shapiro
Word gets out that humanity is doomed: a giant meteorite has been headed toward the Earth for decades, and the government is ill-equipped to stop it. On the final day of human life, Sean must decide who to spend his precious time with. When he opts to hit the road and reunite with a lost love, he encounters a mad society that is rapidly shredding the trappings of civilization.