Hello,
Welcome to the board. I knew a woman (forget her name now) who had MS and MAV who use to post on the Labyrinthitis Facebook group a couple of years ago. This is the page:
https://www.facebook.com/groups/labyrinthitis.support/
However, these are the three most popular Facebook groups for MAV, which you can find here:
https://www.facebook.com/groups/vmpro/
https://www.facebook.com/groups/52537205047/
https://www.facebook.com/groups/labyrinthitissupportgroup/