I think vertigo can be managed. At least in my case it can be. There are meds that mitigate the vertigo. Coincidentally, they also treat anxiety. Benodiazepines like valium are first-rate vertigo drugs and are used for anxiety. You don't take it all the time, just relatively small doses for a day or two to get through the attack.
Yes, vertigo can bring about anxiety. You'd have to be a pretty cool customer to not be anxious when your world is spinning. I know I was anxious the first few attacks I had. Valium is a miracle for anxiety. Also, anxiety, in terms of it being a disorder, would be for people who get anxious about everyday things. But, a severe vertigo attack is not an everyday thing and I don't think being anxious about it is somehow not "normal". This is not a medical opinion, just my own two cents. I think you will be less anxious in future attacks now that you know why they are happening.
My ENT explained to me that as the AN impedes the vestibular nerve, that nerve losses it's effectiveness. When this happens gradually, you don't get sick with vertigo, your brain just makes the small adjustments as needed. The vertigo bouts come from larger, sudden, drop-offs in the performance of that nerve.
The performance of that nerve can be measured with testing. For instance, mine was about 50% when I had it tested a few months ago. Yours is not 100%, but how close it is to 0% you don't know. Eventually it will be 0%, this is virtually certain. The nerve will degrade over time and if you get surgery, they will cut that nerve. When the nerve is cut, it will be at 0%. Once the nerve is at 0%, your brain will compensate for that, and you will no longer get the changes that cause vertigo. The closer you are to 0%, the less chance you have for getting vertigo. That 0% is not as bad as it sounds since the other ear, plus your eyes, plus your skeletal-muscular system pick up the slack to give you your balance. Your balance won't be as good as it once was, but it will be pretty good and you won't get sick anymore.
This is how my ENT explained it to me and my understanding of it all. I think this is pretty conventional thought, but there may different views on this. I don't know how radiation treatment plays into all of this.
So, overall, IMO, I think vertigo can be treated and will ultimately subside. For this reason, I don't think vertigo should be a big factor in your approach to the treatment of the tumor.
Also, you can carry your vertigo meds with you should you have an attack away from the house. I keep one of those pill keeper key fobs on my key chain. In it I keep valium and zophran. Zophran is a miracle cure for nausea and vomiting for me. When I get an attack, I take a zophran which immediately stops the vomiting. Then I take a valium which takes an hour or two to stop the dizziness. The zophran gives me no side effects and the valium leaves me feeling a bit sleepy and very calm. All anxiety is relieved and I am pretty euphoric at that point. It aint a perfect solution, but we aren't in the perfect business at this point. It's as good as it is going to get at that point, and fortunately, that is pretty darn good.