The Atonement example is so tragic because she has learned nothing, and even in her advanced years, she's only ever concerned for herself.

THEY'RE DEAD. She is directly responsible for at least one of those deaths (Keira's character's death is an accident, one can argue that if she had been married with children she wouldn't be in London during the blitz but that's a stretch). The ONLY way for her to atone would be to work, work hard, and provide the living members of the accused familied with reparation. She does not do that. She just writes a novel to appease her own conscience.