Girl in Cabin 10, by Ruth Ware

I could only get thru half this book, due to the protagonist's constant panic attacks and descriptions of vertigo from being on a rocky boat.

"L" was listening on audio and finished the book. She gives it 3 & 1/4 stars out of 5. 

We both found it repetitive. She'd drink, drink more, end up with a hangover, and over and over.