Give honor to marriage, and remain faithful to one another in marriage. God will surely judge people who are immoral and those who commit adultery.
-Hebrews 13:4, NLT
Adultery is a culmination of sinful choices.
I think it is important to understand that we are not dealing with one sin alone when it comes to cheating. Lies and deceptions come with the adultery.
Part of why it is hard for marriages to “recover” from adultery is how the matter is minimized.
Even pastors might try to suggest the illicit sexual act is just a one-off sin. The reality is the cheater had to lie to others and themselves to get to this point.
Often times, I think the deception is the most damaging part of the cheating. The faithful spouse is left wondering when their partner started with the lies and what part of their shared experience was ever real. That is a terrible experience. Trust me.
The cheater could have chosen otherwise–after all, the Bible does not command something that is out of our power to do–yet he or she continued down the broad path of sinful destruction.
Their poor, sinful choices just compounded to create the mess that emotionally and spiritually gutted their faithful spouse. It takes a lot to unwind that mess. Most cheaters lack the moral courage to even try. That is why–I believe–God offers divorce as a mercy to their victims, faithful spouse.