A condition in which a person's identity and interpersonal relationships are centered around a memory of traumatic experience which is objectively false but in which the person strongly believes. Note that the syndrome is not characterized by false memories as such. We all have memories that are inaccurate. Rather, the syndrome may be diagnosed when the memory is so deeply ingrained that it orients the individual's entire personality and lifestyle, in turn disrupting all sorts of other adaptive behavior. The analogy to personality disorder is intentional. False Memory Syndrome is especially destructive because the person assiduously avoids confrontation with any evidence that might challenge the memory. Thus it takes on a life of its own, encapsulated and resistant to correction. The person may become so focused on memory that he or she may be effectively distracted from coping with the real problems in his or her life. (J. Kihlstrom)
She believed that she had been abused by satanists over many years, until she found that she had been suffering from False Memory Syndrome.