In the end

“And you rage and scream and reach through the Force to crush the shadow who has destroyed you, but you are so far less now than what you were, you are more than half machine, you are like a painter gone blind, a composer gone deaf, you can remember where the power was but the power you can touch is only a memory, and so with all your world-destroying fury it is only droids around you that implode, and equipment, and the table on which you were strapped shatters, and in the end, you cannot touch the shadow. In the end you cannot touch the shadow, in the end you don't even want to.” 

-Matthew Stover, Star Wars Episode III: Revenge of the Sith