I thought I'd explained it clearly before. Bella, I can't live in a world where you don't exist.

She reminded me of what it did to her when I left — what it still does to her when I leave. She feels horrible about bringing that up, but she’s right. I’ll never be able to make up for that, but I’ll never stop trying anyway.

Hard to feel confident when you’re surrounded by horse-sized wolves. Emmett Cullen, Breaking Dawn, Chapter 39, p.745

I can feel what you’re feeling now — and you are worth it.

Surely it was a good way to die, in the place of someone else, someone I loved.

So, Bella, I was following your scent through the woods after I'd left your room where I was watching you sleep...Yes that would be quite the ice breaker.

It was not going to be the end of the world. Just the end of the Cullens. The end of Edward, the end of me. I preferred it that way – the last part anyway. I would not live without Edward again; if he was leaving this world, then I would be right behind him.