I think it's wrong and very disrespectful for the wife/husband. However, a marriage can survive it if both are willing to work in making their relationship better and the betrayed person can forgive the one who broke their trust and the person who betrayed is regretting it for real, and it wasn't long-term. Sometimes it would still be best to divorce, so there won't be too much grudge, or if the person forgiving does not actually forgive but stays in the relationship, oppressed, because he or she thinks it's their only option/they think they can't get anything better/they are scared being single.
What is your age?