Edward Bulwer Lytton
From Anecdotes about Nineteen Century Authors

In 1836 Lord Lytton's unhappy relations with his wife had led to a legal separation. In 1839 Lady Lytton published a novel called Cheveley, or the Man of Honour, in which her husband was the villain. She was certified insane in 1858, and spent a short time in the care of a physician, but was soon discharged. She died in 1882.

Note from Wilkie Collins, from Literary Anecdotes