"Keeping your word" is a masculine trait, in men or women.
A person with a feminine essence may not keep her word, yet it is not exactly "lying." In the feminine reality, words and facts take a second place to emotions and the shifting moods of relationship.
When she says, "I hate you," or "I'll never move to Texas," or "I don't want to go to the movies," it is often more a reflection of a transient feeling-wave than a well considered stance with respect to events and experience.
On the other hand, the masculine means what it says. A man's word is his honor.
The feminine says what it feels. A woman's word is her true expression in the moment.