Caitlin Rother and John Hess' Twisted Triangle, to be published in the United States, will highlight Cornwell's affair with former FBI agent Marguerite Bennett, later the target of an attempt on her life by her husband after he discovered her lesbian relationship. Eugene Bennett is currently serving a 23-year prison term.

Notably, Cornwell, a Massachusetts resident, is legally married to a woman, Dr. Staci Gruber. In a candid interview with the UK's Daily Telegraph, she spoke openly about her life, her relationship and her stance on marriage rights.

"I've never been a soapbox person for gay rights," she says, "but now [that] I'm in a same-sex marriage I tend to be more open, because I am outraged that it should be illegal in other states."

"I don't do things that are illegal," Cornwell continues. "I pay my taxes, I give millions to charity, so why am I less than other people?"