This model, of separate ego states, that see different “parts” of the other (the object) explains the extraordinary attachment between the battered woman and her abuser (see Celani, 1995). Model of attachment to the bad object
Fairbairn saw his model of human behavior as universal, that is, he assumed that all children, no matter how benevolent their family environment was, had to dissociate a few intensely frustrating events and, at other times, had to fantasize that their parents had hidden love that they were not displaying; that is, they used the same psychological mechanisms as did children from abusive families, but to a lesser extent. The following analysis is not based on interviews of the four victims, but rather is the result of applying Fairbairns model to the reported behavior of the four individuals. Antilibidinal ego-rejecting object side of the split
When the bank robber and  his accomplice, who was released from prison and allowed to join him, began their six-day hostage taking, the four adult prisoners faced the same environment as do abused children; that is, their lives were absolutely dependent upon the good will of their captors, who had unlimited power over their lives. Their captors were far more important to them than were the police, who were a threat to all of them, captives and criminals alike. Fairbairns model assumes that the captives used the splitting defense to abolish the most terrorizing aspects of their captivity, in order to keep from breaking down into an absolute state of anxiety.
Conversely, the rejecting internalized parent (who is an internalization of the original parent)  holds its ground and endlessly argues that the child was deserving of their condemnation. This dialogue continues in the unconscious, as described in the following quote by Odgen (2010)Neither the rejecting object nor the internal saboteur (the antilibidinal ego) is willing or able to think about, much less relinquish, that tie. In fact, there is no desire on the part of either to change. The power of that bond is impossible to overestimate. The rejecting object and the internal saboteur are determined to nurse their feelings of having been deeply wronged, cheated, humiliated, betrayed, exploited, treated unfairly, discriminated against, and so on. The mistreatment at the hands of the other is felt to be unforgivable. An apology is forever expected by each, but never offered by either (Odgen, 2010, p. 109).The “tie” that Odgen mentions is the emotional investment that each part-ego, or part-object structure, has in fighting with the other. The combination of the libidinal egos tie to finding love in the elusive and ever-shifting exciting object, and the equally motivated antilibidinal egos desire to force the rejecting object to apologize and see his/her value as a human being constitute what Fairbairn called "The Attachment to the Bad Object". The "Bad Object" is a parent or other significant caretaker who has failed the child, but is still cherished by the libidinal ego and fought against by the antilibidinal ego.