The closest we come to is several mentions of her having two split selves (i.e., the nice, people-pleasing Estella and the dominant, vindictive Cruella), going all the way back to early childhood when her mother asked her to suppress all aspects of Cruella.

Does Cruella have a split personality disorder?

Spending far too much time in Cruella's childhood, the film hints at a split personality or possible disorder that's never diagnosed or fully dissected. When it is discussed, it's briefly as a fleeting concern from a friend who says they liked the old Estella, but then continues to support Cruella.

What mental illness does Cruella de Vil have?

Diagnosis: Histrionic personality disorder (HPD): Cruella's desire to be the centre of attention at all times is damaging to herself and those around her. Physical presentation: Cruella De Vil uses her physical appearance to gain attention.