The only way to have a true blessed marriage is for one - not to have an affair, but if you have, then it's time to refuse the devil's ways and let God redeem your marriage. In order to totally be forgiven you must 1st confess it to God, then to your spouse. They deserve to know. It is un-fair to them to sleep with, live with, cook for, work for - etc. with someone who has been with someone else without their knowledge! PLEASE remember the battle - the enemy is out to take dowm marriages - you have to fight for what is right. Lay your fleshly desires down and do what is right. YES, you must repent to God and ask for your spouse's forgiveness as well - there is a spiritual bond between married people! Honesty is the BEST policy!