I agree - the family would never be the same if SHE told so SHE felt less guilty.
For most people who are unfaithful... everything is always about them. It makes sense. She wouldn’t be telling him to make things better for her family in anyway. She thinks it would just clear her conscience. And really, it won’t. She’ll always know what happened... and if it breaks up her family when she tells him and hurts her kids... then she’ll have to live with that too. And she can spend the next few years telling her sad tale of woe to people she meets on Match.com.