Well, without more context, it's difficult to say much about this 'your girlfriend was amazing novel'. It could be a self - published work, or something relatively unknown. Maybe it's a story about a guy who discovers all these wonderful and unexpected qualities in his girlfriend throughout the course of the story.
It's a story that explores the ups and downs of a relationship that lasts for seven years. There are likely challenges, growth, and lots of emotional moments.
I'm not sure, actually. It could be a unique title chosen for artistic or thematic reasons that don't have a straightforward connection to the concept of a name.