Woman Accused of Drowning Fiance Wrote in Diary He Wanted Rough Sex, Prosecutors Claim

At first, the drowning of 46-year-old Vincent Viafore appeared to be a tragic accident after his kayak capsized in the beautiful waters of the Hudson River north of New York City.

His fiancé, Angelika Graswald, appeared on local TV and described what happened. Was it the face of a woman mourning the drowning of her fiancé? Or is she a diabolical killer?

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She said, "I saw him struggling a little bit. He was trying to figure out how to paddle the waves because they were getting crazy - and then I just saw him flip."

The conditions that day were very dangerous. The water was very cold. The water was very choppy and there were also high winds and when Viafore's kayak allegedly capsized, he wasn't wearing a life jacket. The police have yet to recover a body.

But was Viafore's death far more sinister? Police discovered a diary in which Graswald allegedly wrote that he was demanding "rough sex" and "threesomes." She also wrote "wishes he was dead."

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Her behavior since she lost her fiance is also bizarre. Just days later, she posted one video on Facebook doing a cartwheel and other videos show her playing with her pet dogs, cats, and a parrot.

Mike Colvin dated Graswald for over a year. He says it was a really bad breakup, they even fought over custody of their cat.

Colvin told INSIDE EDITION, "If your fiancé passes or goes missing in a tragic accident this seems like a very unorthodox way to display your feelings in a public setting."

He added, "She gets down on the ground after I started the car and lays down and says, and is like, 'Give me that cat!' and I was like, 'You got to be kidding me!' I had no choice but to give her the cat and then I got an alarm the next day."

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Graswald agreed to talk to INSIDE EDITION in the jail where she is being held, but backed out at the last moment and said she didn't want to be interviewed.

She told INSIDE EDITION, "My lawyers told me to change my mind. So, I'm changing my mind."

Graswald insists she is innocent and her fiancé's death was a tragic accident.

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