What was Anakin/Vader's motivation to remain a Sith after Palpatine/Sidious told him Padme was dead? Seemed to me the only reason Anakin went over to the dark side was so that he could save Padme, and control life/death. With that no longer the case, what was his motivation to remain on the dark side? Was it just a "Once you go black, you never go back" type of thing? Sorry for the bad reference pun.