He is the absolute epitome of composure, that Sam Uley. One would think he lives in a plastic bubble; completely ignorant of anything outside.
But everything and everyone has a breaking point.
"I know, Leah. I'm sorry. It's just... too hard to explain. Like love at first sight, only it's exponentially stronger. I have no control whatsoever. I'm sorry. You just have to understand."
Sam said all that with a straight face and a not-so-unusual nonchalant pose. Even when Leah broke down into tears, he was stoic.
"It was all a lie. It was all a fucking lie!" Leah said repeatedly, ignoring the man who just recently broke her heart.
He stood there, looking at her, showing no signs of emotion other than slight pity.
Now, the tables are turned.
"Congratulations, man!"
A series of yeahs followed Quil's acknowledgment; also a few man-hugs and a couple of high-fives. Jacob just announced the existence of a relationship between Leah and himself to the pack. Leah wasn't there; she said she had better things to do.
Between the cacophony, Sam sits at a solitary spot, trying to ensure himself that he has the upper hand in this situation: I have Emily. That's more than enough.
Seth then walked toward Sam, turned his head to the right and whispered into Sam's ear: "I understand."
This time, apparently, Sam's bubble didn't stand the pressure.
A/N: This is pretty vague to me (and I wrote it). But, to clear things up, what Seth meant was that he understands why Sam is jealous.