Every one teaches us to be honest but sometimes honesty is damaging, particularly when it has no relevance with the present. In your case, it was unnecessary confession, which you might have done to get rid of guilt of cheating your future husband. You should always remember that such confessions are always unwarranted and creates issues. No men will ever accept this and if he accepts he may start doubting you any time for such relations. If you want to show honesty to your future husband then be loyal to him through out but never disclose your past which has no relevance to your present.