In Lovely But Lethal, Viveca gives a pretty sad look as Shirley (who's her only DELIBERATE killing) drives away. It's hard to tell from that look just how bad she does or doesn't feel about it, but at least it's there.
I always found her goodbye to Shirley to be more of a sarcastic “little do you know this is a FINAL goodbye” look. It didn’t seem to have any remorse attached to it to me. I find many of the 2nd killings of the blackmailers or the people standing in the way of getting away with murder always turned those murderers into a person who feels justified that the 2nd victim brought it on them-self.