How is lady macbeth submissive

In the beginning of the play, Lady Macbeth seems to be more masculine or the one ‘wearing the pants’ in the play. She was the one who suggested the murder of King Duncan. She also called on the spirits to unsex her or to remove her femininity in order for her to effectively play her role in the murder. However, afterwards the gender roles are shifted and Lady Macbeth becomes submissive. She becomes unstable and unsure. She became insane because she could not handle what she had done. Macbeth keeps secrets from her and goes about in his killing spree.