Looking forward to a new episode of Breaking Bad tonight. Last night I re-watched the previous episode, and while it was superb from start to finish, one line struck me the most: Walt was lying on the bathroom floor, insisting that Skyler never give up the money, and says "Please don't let me have done all this for nothing". It was clear then that once he realized the end was near, he came back to his original motivation for entering the meth underworld: to provide for his family after his death. As despicable as Walt's actions have been, you could at least understand how he rationalized the brutality of his reign as Heisenberg. As long as he knows that his family is taken care of, he can face his upcoming mortality.
Contrast that with Jesse's melancholy: he did all this for the money, period. He did it to get rich, and now that he is, he realizes the cost to his own sanity to have left such a trail of bloodshed was too much. That's why he gave away his money: maybe by enriching someone else's life he might feel that his actions have brought some good to the world instead of just death and suffering.