I think that in moments of clarity they say sorry and they do mean it but when the fog comes back over them that makes remorse impossible. My W has had a few moments of clarity when she has broke down sobbing saying "I'm so sorry, Ive F'd Up" and just holds me tight. I believe that she truly is sorry but hours later when the fog comes creeping back in that makes any signs of remorse impossible. Plus for my wife actually saying the words I'm sorry is very difficult for her and when she finally does say it she has reached down to the depths to pull those words out. it's very tricky and like many people have said you will know the difference when you see it.