She did not want to be known only as the wife of her husband. She insisted on having her own 'identity'. [=on being known for her own qualities, achievements, etc.]
The face of the witness was hidden in order to protect her 'identity'. [=to keep her name from being known]
He has a strong sense of personal 'identity'. [=a strong feeling about exactly the kind of person he is]
(..) Tell him, would you? I got your message. The computer code is the key to this. We find it, we can use it. Use it? He used it to create a false identity so we can break into the records and destroy Richard Brook. Bring back Jim Moriarty again. Somewhere in b, somewhere on the day of the verdict (..)2012 TvShow: Sherlock Title: The Reichenbach Fall Season: 2 Episode 3
(..) No, no, no. He'll have back-up. Do you know what, Sherlock Holmes? I look at you know and I can read you...and you repel me. Can he do that? Completely change his identity, make you the criminal? He's got my whole life story. That's what you do when you sell a big lie, you wrap it up in the truth (..)2012 TvShow: Sherlock Title: The Reichenbach Fall Season: 2 Episode 3