The following case from authors/therapists, Deborah Corley and Jennifer Schneider (2002), is illustrative:
Based on the betrayed wife's sentiment in the case above, she was hurt because the therapist (Dr. Jim) acted ignorant of the ongoing affair and thus became an accomplice of her husband to deceiving and lying to her.
Therapists Glass and Wright (1992) put it this way: "it is inappropriate to conduct therapy when there is a secret alliance between one spouse and an extramarital partner that is being supported by another secret alliance between the involved spouse and the therapist."
Clinicians recommend strongly that on-going affairs need to be disclosed. Author and therapist Karpel (1980) writes, “a current secret extra-marital affair by one spouse is, in most cases, highly relevant to the other spouse, because it involves major issues of trust and trustworthiness, deception, and a violation of reciprocity."