As a child, Monica was criticized severely by her mother for not living up to her expectations. This criticism was always followed by a beating with a whip. As an adult, Monica is generally introverted and extremely shy. Sometimes, however, she acts like a young child, throwing tantrums if she does not get her way. At other times, She is a flirting, happy-go-lucky young woman who says her name is Connie. Most likely, Monica is suffering from:

dissociative identity disorder      

Explanation:

Dissociative identity disorder: In psychology, the term "dissociative identity disorder" is also denoted as DID, and also referred to as MPD or multiple personality disorder. It is distinguished as a mental health disorder that is being defined by the maintenance of two different (at least) and enduring personality phases or states. Dissociative identity disorder is being accompanied by "memory gaps".

Causes: Childhood abuse.

In the question above, Monica is suffering from a dissociative identity disorder.

answer; role-taking;

answer; scientific;