I really am not intending to be unkind to you, but I am honestly shocked at the naivete of this question.
Unless, of course, you consider "being unfaithful" to include failure to pray for and edify their husbands, criticism, nagging, manipulation, undermining, backstabbing, gossip, passive-aggressive behaviour, disinterest in intimacy, unforgiveness, vindictiveness, laziness, dishonesty, disloyalty, removal of children, home, assets and income through the legal system, and a long list of other destructive behaviours.