I'd like to point out that Hermione stopped smiling 1 year before Harry and Ron did. She probably knew the danger long before them <--- I'd like to point out that Harry stopped smiling after year two and Hermoine smiled year three.
The books that I read leave a mark on my soul. I feel like every time you read a good book you get more interesting, smart, brave etc. Every book also carries its own lesson that makes you a better person.