The book I am looking for I read between 2006 and 2010. I believe it was a young adult novel/ coming of age and had a dark blue/purple cover with cursive writing. Looked to be a night image above the sea, maybe?

Plot was about a girl that, I believe, lived in coastal town (maybe northeast) with her family. They ran some sort of store (deli, small grocery or something) and they lived in back or above the store. She had a sister who got pregnant and married. I think her sister might have moved back home after she had the baby. She also had a couple brothers or one who was missing or had died. Tommy is ringing a bell of a character.

The main girl made friends with another prettier girl who was popular, and they were friends with a couple boys. They went to a dance at a local country club or golf club and I remember the main girl having issues over picking out the dress she wore. Something either yellow or with eyelets maybe?

I think someone died or drowned in the book? There was something that happened where a body was found down on the beach…Maybe related to the town trouble maker (his brother ?).

Sorry this is fuzzy and I think some plots of books I read during the same time running together. I thought a man wrote the book and it was out of his normal genre but I could be wrong.

I would greatly appreciate your help! I have been searching for this off and on for years. My friend has recommended it but she cannot remember it either.