The past is not easily forgotten in Persuasion. In fact, those who do have made a complete break with the past in order to reinvent themselves are looked upon with suspicion. And yet hanging on too much to the past can also be a problem. By the end of the novel, the most successful characters are those who are able to learn from their past experiences without being blinded by them.
The reminiscences of Anne and Mrs. Smith suggest that the difference between youth and adulthood is a personal understanding of suffering and loss.
Elizabeth's memory of Mr. Elliot's first rejection suggests that simply living through pain and loss is not enough to bring mature wisdom: one must also learn from one's experiences.