Lightheaded, Foggy Brain

HI Everyone-
I am new to the site and have been reading a lot of posts to try to help me find an answer to my problem. I am 34 years old and have had this problem off an on for basically my entire life. I have been to several ENTs through my life, the latest one thinks I have Menieres Disease.
My symptoms: a lightheaded feeling, no spinning at all, more like feeling like I am on a boat. Also ears clogged that sometimes pop but with little relief. Brain fog, slight dull headache, light sensitivity and sound sensitivity to loud noises. These symptoms come and go with episodes lasting a couple weeks. I have had MRIs and CT scans, all normal. I have had allergy tests with the results being no allergic reactions to anything they have tested on me. Episodes seem to occur different times of year at the same time, for instance the beginning of the summer, anytime the weather goes very crazy and also in the winter. Again though, I was tested for seasonal allergies and all has come back normal. I don't believe I have Menierres disease. I say this because I do not have any spinning sensation at all, just an very off balance feeling. Also, while my ears do feel full, I am able to pop them with occassional relief which I believe is not possible with Menierres. I don't think that foggy head is a symptom of Menieres. Also, this is something I have had for most if not all of my life.  Because of these problems I know I also have anxiety, not knowing what triggers it and being mindful to stay away from any activity that may make me vulnerable. I seem to get motion sick much more easily than most, specifically if I am ok driving in a car for  awhile, however when we reach a destination I get very off balance and light headed. During the day I am much better when I am moving around, when I sit down the off balance becomes worse. There doesnt seem to be any particular head position that makes it better or worse, I do know that I get more off balance when I look up. What I think I am leaning towards is Eustachian Tube Disorder or perhaps even TMJ? (My jaw cracks fairly often when I yawn or chew).
I am frustrated by my MD's, they dont seem to think this is as much of a problem and a hindrance in my life as it is, although I have lived with this for most of my life, now more than ever I am determined to figure things out. I was frequently treated for what they thought were sinus/ear infections as a child. THe MDs seem very non-chalant. I know I am more fortunate than others with my balance issues and I am grateful for it. I work and have a fairly normal life but there are also things I don't do because I am nervous that there are some things that might trigger it, particularly travelling long distances, either by air or car. I know this is a long post but I wanted to tell as much as I could. Thanks for listening. I live in Northern NJ near NYC. Any advice or guidance anyone can offer would be greatly appreciated. Thank you again--