We can tell from the title of Ghosts that the past may play a role here. The spooky, creaky Alving house is collapsing under the weight of the past. There's a memory of a misbehaving father, compounded by Mrs. Alving's memory of every lie she had to tell to keep his real life a secret. Mrs. Alving wants to bury the past, but when her son returns with the past in his body, her mission changes. Instead of a final burial of her husband, Mrs. Alving facilitates an enormous recovery of the memory of his life. Her new understanding of her husband's life-loving nature – and her role in repressing it – transforms her understanding of herself.
Through the process of facing her son's unwelcome resemblance to his father, Mrs. Alving rehabilitates Captain Alving's memory.
In Ghosts, the past is always present.