rake over the ashes

rake over the ashes {usually in continuous tenses} (to think about or to talk about unpleasant events from the past) — ворошить прошлое, копаться в прошлом;
~ бередить старые раны
Also rake over the coals and rake over the past

There is no point in raking over the ashes now, you did what you thought was right at the time. (CIDI)

There's no point in raking over the coals — all that happened twenty years ago, and there's nothing we can do about it now. (CIDI)

Related vocabulary
[let bygones be bygones]