[Originally posted at Ana Mardoll's Ramblings.]
Edward and Bella are talking in the hospital, Edward has broken his promise to explain things to Bella, told her she is delusional, and assured her that no one will believe her, she explains that she has no intention of telling anyone, Edward asks, "Then why does it matter?" and that is where this scene diverges from canonical Twilight.
Edward: Then why does it matter?
Bella: You want it spelled out for you?
Edward: It would help.
Bella: You lied to me. You tried to gaslight me. You lied to me.
Edward: You already said that.
Bella: It was a separate instance. You made a promise you never intended to keep. You had me lie for you, you lied to me, you lied to me, more gaslighting, you were a dismissive asshole, you lied to me.
Bella: So what possible reason do I have have to keep on lying for you?
Edward: Don't know, don't care, I'm just going to shoot self in the foot more by sending off signals that convince you that you're definitely onto something.
Bella: You do realize that, right here right now, I'm already on your side keeping you secret for you and the only thing that you could possibly do to threaten your situation is to convince me that's a bad idea.
Edward: If we get along and we're nice to each other there will be no tension. We need tension.
Bella: You are such an ass.
Edward: See? Tension.