"Unfaithful" means not being loyal, trustworthy, or honest in a relationship or agreement. It describes someone who has cheated or betrayed someone's trust. Full definition
The partners of unfaithful spouses almost always experience the trauma of discovering the betrayal, and are often re-traumatized by their partners, pastors, or misguided couples therapists by being told to «quickly forgive and forget» and «not talk about it anymore». (counselingatl.com)
Researchers have barely scratched the surface in terms of investigating the effects of cyber-infidelity on committed relationships, especially related to discovery methods of unfaithful partner behaviors and the resulting consequences on the relationship. (scienceofrelationships.com)
When unfaithful wives were younger than 31 years old with no kids, they were more likely to divorce after an affair. (bestmarriages.ca)