Answer:
Working through past trauma and integrating alternative personalities into one personality
Step-by-step explanation:
Dissociative Identity Disorder (DID) is a mental illness which is characterised by two or more than two frequently recurring personalities. The personalities are usually accompanied by memory gaps. It is generally caused by trauma though genetic factors may also be responsible.
Therapy for DID is very critical because it can better or worsen the problem. Many times the altering personalities can react violently to therapy because they are scared of disappearing. It is important to explain to the host that all the personalities stem from the same person and therapy wont destroy their existence. As the patient revisits trauma and finally gets a closure the multiple personalities can be successfully integrated into a single one.