Kristoff St. John's Fiancee Kseniya Mikhaleva Posts Heartbreaking Message Following His Death

The late Kristoff St. John's fiancee, model Kseniya Mikhaleva, is mourning the sudden death of the actor. 

The late Kristoff St. John's fiancee, model Kseniya Mikhaleva, is mourning the sudden death of the actor. 

The Young and the Restless star's attorney, Mark Geragos, confirmed St. John's death to ET on Monday. The cause of death is currently unknown. He was 52 years old.

Mikhaleva and St. John had been engaged since last August. On Monday, she shared a picture of him kissing her on the head on Instagram.

"How did it happen??? How??? Why did you leave so early????" she wrote. "And left me alone ..... I can’t believe ... you were everything to me .... you were a loving father, a loving man,.....how ...love?? We should doing a lot of things in future......."

She also wrote on her Instagram Story, "Why you are leave so early???? Why ... you are always in my heart."

Instagram

Mikhaleva and St. John announced their engagement on Instagram last fall.

"?❤️ special day 31.08.2018," she wrote next to close-up of her ring.

"She said yes @ksumik," St. John also wrote.

Over the holidays, they shared happy selfies together in Moscow. 

Aside from his fiancee, St. John leaves behind two children, Paris and Lola St. John. His 24-year-old son, Julian, died of a reported suicide at a mental health facility in 2014. 

In 2017, St. John and his ex-wife, Mia, spoke with ET about struggling with their son’s death. Watch below:

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