Amazingly enough, I'm actually pretty comfortable about all the planning-related things. There are still a few open questions, tasks to finish (like making up the seating chart, which I'm actually looking forward to -- it's a big logic problem!), and missing RSVP cards, but for the most part everything is settled, the important decisions are made, and mostly what I have to do now is sit back and let it happen. And maybe that's the hard part -- letting go of all the details and accepting that the day will happen, that even if little things go wrong, we'll be married at the end and that's the important part.
Everyone I've talked to in recent weeks have marvelled at how calm I seem. That's partly true and partly a front -- I want to be calm about the whole thing, so I make an effort to feel that way, or to act like it even if I'm not. It seems to be working so far, and I hope it lasts.