How did Richard get away from the Mord-Sith collar, how are Mord-Siths created and how strongly does Richard feel about ever wearing another collar?

Richard was able to kill her; she was glad someone had the strength to free her from her own prison. Richard wears a necklace because Denna asked him to wear it and remember her as something other than a monster. Mord-Siths are created by torturing a woman, and Richard was one of the few that could understand her. Richard tells Kahlan that he will die before he ever puts on another collar.