The authors address their article to the understanding of the impasse in the work with the couples in which we have to deal with the defense mechanisms like splitting, or projective identification, often connected with personality disorders. This kind of couples is characterized by recurrent acting out of conflicts. The paper presents systemic and psychoanalytic (mainly in the object relation theory) perspectives as the basic theoretical framework for the analysis of described phenomena. It refers to the concept of personality disorders diagnosis in the setting of the couple therapy. It presents how the relation can change the diagnostic impressions of the personality structure and how it leads to problematic clinical situations. The paper presented case vignettes illustrates changing role of the therapist in consecutive stages of the therapy. They show the impasse in the therapeutic process and the ways how the therapist is dealing with the problem. The therapist of these couples struggles with many dilemmas and a recurrent question concerning the continuation of the treatment. In the summation authors conclude on the practical use of the systemic and psychoanalytic paradigm in the analyzed clinical situations.