Interesting topic.. I know I have read a ton of sentences and passages that are so good that I just have ro re-read them. Unfortunately, I've only recently started to mark these in books that I own or write them down from books that I'm borrowing. There are a couple of authors that really stand out for me. One is Charles de Lint and the other is Robin Hobb.
Charles de Lint is able to put words to feelings that I've had for a long time. I tend to say things like, "That's exactly how I feel!" when reading his books. Here are a couple of quotes in particular:
"I have no vices. I have no strong political or religious beliefs, I'm not given to causes, and I've always treated people the way I'd want them to treat me. Decently, with a little distance. It means I have far more acquaintances than I have real friends"
Along the same line...
"Nobody else seemed to measure up. But now she found herself wondering, was that the real reason, or was it more that she didn't measure up? That she couldn't face up the to the responsiblity that having friends involved? But that wasn't it entirely either. The thought of making friends scared her so much she didn't even bother to try anymore, because it was easier to stay aloof and not get hurt".
On a lighter note:
"To discover who you are, first learn who everybody else is - and you're what's left".