There is no confussion with lady Macbeth on how she feels about killing Duncan. She is willing to do whatever she. Her strength is shown when she asks for her femininity to be stripped from her. "Unsex me here...come to my woman's breast and take my milk". Her strength is shown here as back in the 11th century, a women's purpose is too look after their children but lady Macbeth is that thirsty to become queen, she is throwing her chances away, giving her life no purpose. However her masculinity gives her strength as she is thriving off evil.
In the play as a whole Shakespeare presents lady Macbeth as a strong and influential character until act