Your eye problem is common. You have your vestibular system, your muscle system, and your eyes that balance you. All three must match up in your brain. When they don't, you get a balance problem. If you have an AN, your vestibular system is under attack from the tumor, and telling your brain you are not balanced. But, all along, your other vestibular system is saying you are just fine. Your muscles are receiving messages you are not balanced from the brain, but your muscles are sending out messages back to the brain that you are balanced, and your eyes are trying to latch onto something trying to figure out what is really going on. Massive confusion going on in your brain!
This is when I started vomiting all the time. I had surgery 10 months ago, and my eyes still wander around sometimes, but not much. I rely on my eyes BIG TIME to balance. At night I have to have some lights on or a flashlight to walk. I could not drive a car for a while, even in the day. It felt to me that my eyes were spending so much effort to balance me, that they were not really "looking" at things, they were just trying keep me up-right.
Hopefully you don't have an AN, but if you do, you are in the right place. Your brain will begin to adapt to all of the new confusion, and you will on the way to getting back to normal. Good luck to you.