The role of women in Shakespeare's tragic play Macbeth is complicated.
When first examining the women in the play (Lady Macbeth, Lady Macduff, and the witches), one sees that they all question the ability of the men in the play. Lady Macbeth questions if Macbeth is man enough to do what needs to be done to take the throne (murder Duncan). Lady Macduff questions her husband's decision to leave his home and family for England. The witches, after being told by Hecate, question if Macbeth is coming to them for good reasons (friendship) or if he is coming to them for his own benefit only.
The role of women, underneath, is one which has been historically identified as the woman being the backbone of the home. She, used universally, is the one who keeps the home fires burning, takes care of the private sphere, and supports her husband. While on some aspects the woman in Macbeth do this, in other ways (questioning the role of the man), the women in the play tend to be the stronger gender. (Lady Macbeth knows that she is cold enough to take the throne, Lady Macduff can get any man she wants, and the witches are responsible for putting the entire movement into action.)
Underneath it all, the women tend to be the stronger sex, until their weakness (mental imbalance, physical weakness, and emotional attachments) come to the surface.