In family psychotherapy, the coterapeutical couple is involved in a game of mirroring that highlights the presence of isomorphisms in the systems to which it belongs: coterapeutic, therapeutic, family of origin, therapist/ partner and supervision system. Consequently, the differentiation of the therapist influence the relations of the systems to which he/she belongs. These disturbances create tensions in relationships that might be subject to rimodulations, momentary or permanent breaks. The changes that occur in extratherapeutical systems organized as complex systems, affect the therapeutical path and vice versa in a recursive manner.
Keywords: Isomorphism systemic, mirroring, cotherapy, couples therapy, differentiation.