[She's going to play along, because she'd rather be caught joking, then being serious.]

Sure Dave, it means a lot. All of the lots. All of them. This room sharing is oooooooobviously serious business here. Or else we wouldn't have done it for months and months. But married? That's like a big step, right? And aren't we still young?

[She still doesn't even know what marriage is. Just the little bits John has told her.]