It's not always a happy ending

I've finished with the second story book I borrowed the other day. This one is called 'The Wrong Boy'. It's aboutthis posh girl named Grace Foster-Bryce. She used to lived in a huge house like really huge with a swimming pool, tennis court and there is about more than 7 rooms in the house. One day her dad was sent to jail for fraud and she now lives in an area where there are smokers, street people, basically they are un-posh liked. She then falls in love with this boy,Jay Jones, who lives a life different then she does. They loved each other no matter how different their lives were. Not long after, Grace has to move back to her posh life with her grandmother. Grace and Jay then had to break apart unwillingly. The end. What an ending right? This shows that not all stories have an happy ending.