My co-wife likes to tell me at length about her private matters with our husband. How do I set boundaries?

You have the right to set boundaries gently when such sharing adds to your burden or touches on matters that should stay private. Listen politely, then change the subject or say kindly, for example: ‘I think it's better that we each keep what's between us and him to ourselves.’ This is not arrogance, but protecting the peace of both of you. Also avoid responding by telling her about your own home by way of comparison. If the sharing is meant to show off or to hurt, cut down the time you spend talking and let your husband know if necessary. Keeping marital matters private protects everyone's dignity. See co-wife relations.