Book age

Maybe it's from reading so much young adult fiction, but I always assume when I read regular books that the characters are all significantly older than me. I just finished a book written by Nora Roberts about two people who were in love at 18, and reunited 10 years later. Short cute little Christmas love story, kids everywhere, everyone is married. And then I put it all together in the shower, the buggers ARE MY AGE!!! Good grief! How many times did I read, "back when we were young and reckless/careless..." I still am young, reckless AND careless. And happy. Thank you very much.