I'm looking for a Pacific type of book

I'm looking for an audiobook that once the book is over it doesn't mean that the character can go back to what they were. I mean like in books where they're trying to defeat somebody. Trying to figure out a mystery or they're trying to reach a goal. That when they achieve one of these things once they've done what they need to do. Things are going to get better now and they can look on to brighter futures. I'm looking for a book where that's not a possibility where once it's over they can't go back to what it was before they can't become the people they once were. They've done too much, lost too much or sacrifice too much. to let whatever they've done go this will be with them for the rest of their lives. I hope that my description from what I'm trying to look for specifically described it enough. Hopefully there's something out there like this.