Helena is the character that has suffered the most come to think of it.
She has literally been through one hell of a roller coaster of emotions.
Her father got killed by Bayman first.
Right after, Christie just waits for the climax of her recital to shoot her.
Then here goes Ayane, trolling on her mother's passing in the same opera house in flames (for fun), and letting her mistake her for the murderer as a result.
If Kasumi that is the face of DOA is not in it, that's going to be the last nail in the coffin.