Cheaters Anonymous Community Group
This is a support group for cheating spouses looking for understanding and strength. Betrayed spouses are welcome to post ONLY if they can do so in a supportive manner (no bashing...these posts will be deleted), and please do not comment on 'Cheaters Only' posts.
As for the sister in law - I don't expect any cultural differences. It will be exclusively her personal experience/knowledge/attitude that will determine her reaction. In every country you will find people with very different type's of attitude towards infidelity. Also - you might be surprised - she might have the history (or other members of your family) that you would never expect.....
Good luck!
She told me who he was and that was that. My dad however never knew for sure. I told him. He kinda assumed but didn't need to know any details. That is common throughout his family. Beleive me there could be plenty of skeletons in her closet too. Don't be fearful. Her response will likely be respectful and stoic.