The Ghosts of Pemberley by Catherine Bilson

Elizabeth Bennet sees dead people.

She always has. With the help of her family, and the firm conviction that the dead are mostly just people who need a little patience, she has managed her gift in secret her whole life.
Marrying Fitzwilliam Darcy is the greatest joy of her life, and her greatest risk. Pemberley is ancient, grand, and very, very haunted. Elizabeth knows she will have to face whatever is waiting for her there, and she knows she cannot hide her secret from her husband forever. She just needs to find the right moment to tell him.
She does not get one. Pemberley is teeming with centuries of opinionated spectral residents, headed by a formidable great-grandmother who has very specific requirements for the new Mrs Darcy. And before Elizabeth can even begin to navigate her new household, living and dead, she meets the one ghost she never expected.
Her father-in-law. And he has something terrible to tell her.
George Darcy was murdered. Poisoned by his own godson, George Wickham. The same Wickham who is now married to Elizabeth’s youngest sister. And George cannot rest until his killer is brought to justice.

Elizabeth cannot reveal what she knows without risking everything. In 1812, a woman who claims to see ghosts could lose her marriage, her freedom, and even her life. She cannot prove George was murdered without evidence no court would accept. And Lady Catherine de Bourgh has just arrived at Pemberley, sharp-eyed and hostile, watching Elizabeth’s every move.

A poignant, darkly funny Pride and Prejudice continuation about love, justice, family secrets, and ghosts who absolutely refuse to be managed.