This had a great premise that was well-developed on both a world-building (of sorts) and more intimate level. It reminded me of The Leftovers by Perrotta. Even though the narrator was 11, it definitely read like an adult book and not a kids or teen book - which is a bit of criticism in that it didn't capture that age quite as well as books written for kids and teens. But the story was very compelling and it was a quick read. 
 One funny moment: On page 37, in reference of Michaela, was the line, "it was hard to keep up with all her Jasons and Brians and Brads" and I had to look back to make sure the book was set in present-day and not the 1980s.