Do to others as you would like them to do to you.
-Luke 6:31, NLT
If you know someone is cheating on their spouse, do you tell the faithful spouse?
In a word:
YES!!!
Now, that does not mean you have to tell them immediately. However, I figure the Golden Rule applies here. Would you have wanted someone to alert you to your Cheater’s sinful behavior?
I would have.
It is actually sickening thinking back at people who probably knew but never told me. I bet many here can relate. It is part of the multiple betrayals that come with dealing with a cheating spouse–namely, a community that conspired to protect Cheater through their silence.
Tell. But choose your timing and way wisely.
Talk with your lawyer about how it may or may not impact your divorce and/or custody battle. Maybe wait until things are settled? Also, be sure that you are safe to do so–physically and financially.