Originally posted by Darth Vicious
Even more so than Jane? Her only crime was being a biotch to Walt and being a junkie. Jesse tends to be a biotch himself sometimes, he is a junkie and killed before.
He only let her die, which was terrible but hardly comparable. Besides which is that he obviously did that FOR Jesse, to keep him close and also so he wouldn't throw his life away with her. As Jesse later admitted, they probably would have OD'ed in a week with all that cash anyway. Jesse has always been the one aspect of his life where Walt will do the right thing in the end. Yes he's abusive to him, but he's also risked his life for Jesse and done loads to protect him and keep him close.
Walt killing him would signal Walt truly becoming irredeemable.