After Burke said to Sam in the diner, about Laura's arrival, "Start sweating, Sam!"... immediately I had a mental picture of Burke saying that, followed instantly by every pore in Sam's face bursting forth with its own streams of water/sweat, shooting several feet across the room, in all directions! Well, made me LOL, anyway...
I liked that Laura admitted to Burke that he had understandable reason to be bitter. It's the only acknowledgement of the real nature of the accident that he's had from anyone. When Burke says David's the kind of kid the two of them could have had, Laura answers significantly": "Exactly the kind." Hint hint.
BIG SPOILER:
[spoiler]Did the burning in Arizona press the reset button on her sanity, enough to get herself together and come to Collinsport? Was that why she did it? I think she never stopped being insane, though...[/spoiler]