A recent US study published on extra-marital dating site Ashley Madison sheds light on some women's reasons for cheating. This survey was conducted on a panel of 1,047 women registered on the Ashley Madison site.
Recall that this is an extra-marital dating site, and the results are to be taken with a grain of salt. The point isn't to draw any generalizations here.
Interestingly, 56% of women surveyed said that cheating on their partner increased their confidence and made them happier.
They also explain that they cheat on their partners because they feel lonely (37%) and they feel a lack of intimacy with their significant other (49%). 25% of them say they do not feel wanted by their partner.
Now, we hope to see a survey of their male counterparts!