Cassandra Peterson -- AKA Elvira -- Reveals 19-Year Relationship With A Woman In New Memoir

For 40 years, Cassandra Peterson has lived in the shadow of her famous alter-ego Elvira... and so has a big aspect of her personal life. Until now.

In her new memoir, "Yours Cruelly, Elvira: Memoirs of the Mistress of the Dark," Peterson reveals for the first time publicly that she's been in a relationship with another woman, Teresa Wierson, for nearly 20 years.

The two first met back in 1995, at a gym where Teresa -- or "T," as she refers to her in the book -- worked as a trainer. Peterson was instantly attracted to her, but first thought she was a man.

"Dark and brooding, he gave off such intense energy that when he crossed the enormous gym floor, the waters parted and people stopped in their tracks to stare," Peterson writes in the book, of seeing T for the first time. "A typical sexy bad boy, he was unaware he was so charismatic that he'd garnered his own unofficial fan club. Watching him from the safety of my treadmill made my heart beat faster and the time pass much more quickly. I mean, c'mon, I was married, not dead."

When Peterson's trainer left the gym, she was then paired with her crush and realized T was a woman.

"A former bodybuilder, track runner, and cyclist, she was an incredibly sweet person, despite her tough exterior. She had the ability to make something even as mundane as working out fun, and we trained together three times a week for the next six years, striking up a close friendship along the way," she writes.

When Peterson's marriage to Mark Pierson fell apart and ended in divorce, the two grew even closer -- until she shocked both of them by kissing her after a night out.

"One such evening, after coming home from a movie, I told her goodnight and suddenly felt compelled to kiss her -- on the mouth. As shocked as she was, I think I was even more surprised. What the hell was I doing?" she wrote. "I'd never been interested in women as anything other than friends. I felt so confused. This just wasn't me!"

"I soon discovered that we connected sexually in a way I'd never experienced, and after a while it became clear I was falling in love with this beautiful, androgynous creature who'd appeared on my doorstep, like an angel, just when I needed someone most," she added.

The two have been together for more than 19 years now and, after calling T her assistant for ages, Peterson's ready to live out in the open. She added that she kept the relationship hidden for so long because she "felt the need to protect Elvira in order to keep my career alive."

She's clearly over that mindset now, adding, "If something as personal as my private relationship causes some fans to no longer enjoy my work, or if a company chooses not to work with me because of it -- well, all I can say is, 'F--- 'em.' That's their problem."