Aww, Marilyn, you already re-watched the episode. I still have to do so. I'll see if I'll manage today...
But yeah, that's been the moment she decided to go against Red. It's what she tells Red.
And still I don't understand it. Why then?
And true, her statement was a lie because in the end she even betrayed Liz.
She's even responsible for Tom's death, the death of their little family because of the actions she started before her death.