Hi and welcome to our special club that no one wants to join! This is a great place to find information, inspiration, comfort and you can also vent your fears and frustrations. We've all been there, done that to different degrees.
You haven't asked, and you seem already set on your method of treatment, but I'm going to tell you that unless your AN is in a precarious location (like very close to your brain stem), you do have options available to you besides surgery. My AN is a bit bigger than yours as it is closer to 2x2x2 and I had radiosurgery. I am only mentioning this since you seem frightened by surgical complications that could arise. We respect each other's method of treatment, so I'm certainly not trying to change your mind, but I'm wondering if you were given the opportunity to explore a different route. Just a thought!
Whatever you decide, I wish you the best in your treatment and recovery. It's not the end of the world to get an AN, but it changes our world somehow or another. It's okay to be angry, frightened, sad and befuddled. I return to angry now and then!
Kindest regards,
Sue in Vancouver USA