Have you gone to an ear doctor / neurotologist? Please don't wait any longer; you don't have to suffer through this. My vertigo was do to perilymphatic fistulas, or tears in both inner ears. My doctor operated on the right one last Tuesday, and I've hardly experienced any vertigo at all.
According to the literature I received, the fatigue is due to you trying to compensate and reconcile all the conflicting information coming in from your eyes, vestibular system and other senses. Simple activities become like LSATs. Higher order brain function went out of the window on bad days, and I had to incorporate a lot of strategies to help me complete tasks at work, like take notes of everything and complete tasks given to me immediately because on a bad day, I wouldn't even remember to check the notes. Here are some other tricks I use. You'll need to develop your own bag of tricks:
Talking myself through tasks helped a LOT because it caused me to focus on my voice which did not shift position like the paper in front of me.
To help with concentration, I did the same thing: I would say what I was typing or about to type. Even then, I often lost my place or train of thought, but it was easier remembering something that I said.
Post-Its in bright colors are my best friend, which I place on my laptop.
Additional Post-it software and calendar alerts for EVERYTHING that needs to be done (especially appointments) are a lifesaver.
I take really good notes during meetings, especially professional development and training so that I can refer to them later. Included are procedures outlined and in good enough detail.
Complicated tasks like schedules, meeting planning, summaries, etc. are done with brainstorming and graphic organizers to help you think and tie together different elements in an easier-to-process format than paragraphs.
I asked people to send e-mails instead of verbally delivering requests; e-mailed requests are handled, off-the-fly verbal requests are usually not (see above).
I was allowed to drive, so I had to figure out the least stressful way to commute to and from work.
I configured a driving strategy where I could change lanes at points that caused the least stress. I drive to prevent surprises in front of me or on the sides, because fast head turns are a no-no. I avoid bunny-hoppers (drivers who floor the accelerator then stomp on the brakes) for the same reason. I stayed behind either consistently fast or consistently slow drivers who tended to brake gradually and use signals (signals are my best friend!) The fewer the stoplights, the better. Oddly enough, GPS is a helpful tool even for familiar routes. When having a bad commute (too many surprises), I allowed myself to get angry but did not allow it to translate into aggressive driving. I realized that it wasn't necessarily the traffic, but frustration with working harder to process information while driving, and bottling up anger is a big no-no.
Speaking was difficult for me, especially on bad days, so I got used to thinking and practicing things that I needed to communicate beforehand and using a dictionary or thesaurus when unable to pull a word or definition out of the fog of my mind. The aforementioned notes I took also helped to keep practicing the vocabulary and sentence structures I am used to using while speaking, but unable to use because of the condition. I also communicated a lot more in writing.
Finally, my wonderful doctor recommended I take T-Bio, which is an herbal supplement that helps alleviate vertigo by sending blood to the working parts of the ear and easing nausea.
No matter how badly I felt, I never passed up a chance to have fun. I pulled myself out of the bed and hung with my friends whenever possible.
I drank water and focus Vitamin Water religiously while at work, and always kept some gingerale on hand. I did not try to cram meals down for lunch, only light snacks throughout the day unless I was absolutely starving.
I kept Alleve Sinus Headache on hand for pre-thunderstorm sinus attacks, but stopped taking it because the T-Bio was effective. I also modified my activities on the day before and of a thunderstorm or dramatic air pressure change.
I went to sleep the moment I felt sleepy. Lack of sleep kicks up the vertigo... a lot.
I asked people for help: reminders, redirection to what I was doing or saying, etc. I asked co-workers to rephrase something if I didn't understand, and persisted to ask questions until I was sure that I understood everything (processing complicated tasks given suddenly are difficult on a bad day, so I uses questioning strategies to get information I needed or be reminded of something I forgot and didn't know I forgot).
Etc. ad nauseum...You get creative after a while. I've had vertigo for years.
While you're waiting to get this fixed, start thinking of ways to lessen the cognitive burden of certain activities and get into the practice of helping yourself get through each day successfully. Don't get depressed or anxious; just get used to working harder and being more strategic about your actions. Vertigo is strenuous and frustrating, but very funny at the same time. Vertigo ensures that you never have a boring day. I mean, everything is interesting to watch, and in the end, it builds character.
Please share with me your progress in addressing this issue. I hope that you get better soon. Just don't be its victim. Hopefully, concentration and determination will get you through each day.