Congrats!! Been there, done that (without the surgery), and it's a great milestone! It's weird how our brain still thinks that we're as big as we used to be! I know what you mean about the clothes sizes (why I'm selling a couple of gun belts!). You have to get an entirely new wardrobe!
I'm familiar with the surgery, back in NY when I was in the medical field, I worked in the OR with a Dr. that was one of the first to do this procedure in the 80's.
Stick with it, keep to the required diet. Someday, I'll tell you a crazy story about a patient who went home and stuffed herself with pizza, needless to say she came in that night for emergency surgery!
It'll take time, but eventually your brain will 'catch up' with the "new you"! Again, kudos and congrats!!