Truth
Before Kraven had told her, in that vital moment when Michael was gasping out his life (death) in the throes of death (oblivion) – from Kraven himself, the divine irony – the reality behind her private massacre, she had known the truth.
But not so much known, more like sensed. The marks on the necks of her family were slashes, not the deep trauma fatalities that she has become all too accustomed to from the lycans. After Viktor had killed (birthed) her, she had caught a faint smell of her family's killer, just barely eluding her freshly turned senses. She had thought that the stench was lycan, after the news Viktor had told her. But, when Kraven told her unbelieving ears her life's lie, all those years after, she finally realized.
It was her.