When I started this book my thoughts were a little messed, but I actually liked Chase and his story could be a better. For me Ava was too boring and she had the best life, even a great family but could never care enough for them. I think Chase was trying to get away from all those McKay and decided to follow the bull riders competition.
So their relationship was actually the best thing in the book, because both of them found some inner strengh and made the changes necessaries in their lives for the future. Chase even made it possible to save people from horrible death. I liked his changes better, because Ava was a spoiled girl and she didn't change much, only embraced her softer side.