These are all people who stay involved or wish to stay involved with people who betray them. Emotional pain, severe consequences and even the prospect of death do not stop their caring or commitment. This means the victims have a certain dysfunctional attachment that occurs in the presence of danger, shame, or exploitation. There often is seduction, deception or betrayal. There is always some form of danger or risk.
Some relationships are traumatic.
Take, for example, the conflictual ties in movies like The War of the Roses or Fatal Attraction. Abuse cycles such as those found in domestic violence are built around trauma bonds. So are the misplaced loyalties found in exploitive cults, incestual families, or hostage and kidnapping situations. Codependents who live with alcoholics, compulsive gamblers, or sex addicts, and who will not leave no matter what their partners do, may have suffered enough to have a traumatic bond. Take Cheryl as an example.