Hi!
I'm sorry I am not post-surgery so I can't give you a happy story about how easy my recover was or how wonderful it is on "the other side." I just wanted to tell you that you are not alone. I'm having my surgery in a couple of weeks to correct my open bite, and when I start imagining the surgery and the days immediately after, I also get scared out of my wits! I
When I first got my surgery date, I was ecstatic. I had been waiting years to be ready for surgery, but then that feeling wore off and was promptly replaced by nerves!! I can tell you that, as I get closer and closer to my surgery date, I have gotten increasingly obsessed and reading everything I can get my hands on. This has kind of only exacerbated my nerves, so I am trying really hard to distract myself with things besides reading and thinking about surgery. When I do think about the surgery, I'm trying to focus on all the positive things that will eventually come of it--like biting into pizza and sandwiches and not having a big gaping hole when I try to smile!

Oh, it also helps (me, at least) to think about having time spent aside to relax, watch movies, read books, and hopefully enjoy smoothies and milkshakes. I try to look for silver linings, and this is a nice one for me because lately I have not had a lot of lounging time for myself.
Anyway, after reading tons of orthoblogs and asking questions from post-surgery people, it seems that for most people the worst parts of the experience are over in the span of a few days. I am sure post-surgery folks can chime in with more helpful feedback here. Best of luck to you!!!