Right answer is: "[Cheating is] to be emotionally or physically unfaithful. There are degrees of cheating from sexual betrayal of a partner or spouse to affairs of the heart in which a member of a relationship has a secret, emotionally meaningful relationship outside his or her primary one." — Jeffrey Rubin, Ph.D.Jan 15, 2019
The title of my answer is 8 Relationship Experts Define Cheating
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