“Micro-cheating,” an internet-era term for small acts of betrayal, is the subject of an endless stream of content on social media such as TikTok and Instagram. Because so much of it happens online, couples are monitoring and investigating each other’s digital habits for signs of disloyalty.

The wealth of digital interactions at our fingertips make it tough to tell which ones are appropriateand which cross a line. With the new, contradictory rules of the road come violations of privacy and inappropriate surveillance, some relationship experts say. How much of a partner’s online life are we entitled to, and how much privacy is appropriate to give up inside a relationship?