One should firmly oppose and condemn it. Such a story promotes immoral behavior. You could tell the person that cheating is wrong and that they should respect the institution of marriage.
Cheating on your husband is never okay. Marriage is based on trust, and when you cheat, you break that trust. It can cause a great deal of pain and damage to your relationship, not to mention the ethical and moral implications. So, no, it's not okay to share such a story as if it were a positive thing.
Cheating on your partner is never ethical. It violates the trust that is fundamental in a relationship. Even if you felt 'great' in that moment, it's likely due to short - term excitement or novelty, but in the long run, it will cause a lot of pain for your hubby and can damage relationships not just with him but also with family and friends who may get involved once the truth comes out.
One should not participate in spreading it. If possible, encourage those who are spreading it to stop as it is an invasion of privacy.
If you hear someone say this, you should firmly correct them. No one should tolerate such disrespect towards a partner. You could say something like 'That's a very unkind and inappropriate thing to say about your wife.'
The husband should first try to stay calm. Reacting impulsively with anger or aggression won't help. He could listen attentively to his wife's story, understand her reasons (although cheating is wrong, there might be underlying issues in the relationship). Then, he needs to communicate his feelings honestly, like if he feels betrayed, hurt or confused. It's a very difficult situation, but communication is key to deciding what to do next, whether it's trying to work through it in therapy or making the tough decision to end the relationship.
Most people feel guilty. For example, a student who cheats on a test for the first time might feel really bad about it later, knowing that they didn't earn their grade fairly.
If you hear such a story, the best reaction is to firmly and politely stop the conversation. It's not something that should be discussed. You can say something like 'This is a very private matter and we shouldn't be talking about it.'
React with disgust and disapproval. Don't allow the story to be spread further. If possible, try to correct the wrong perception of the person sharing the story. If it's a more serious situation, you could even seek advice from other mutual friends or an authority figure in the community on how to handle it properly, all the while keeping in mind the well - being of your friend and his relationship.
Politely distance oneself from the situation and the person sharing it. Maybe change the topic if possible. There's no need to engage further as it's an inappropriate topic.
He should first stay calm. Reacting impulsively might make the situation worse. He could then ask for details like why it happened and if there are still feelings involved with the other person. After that, he needs to think about whether he can forgive her and if their relationship can be rebuilt.