Not sure if this will help anything, but I started to have severe anxiety when flying a couple of years ago, to the point where I almost just left the airport right before boarding. This just happened out of nowhere, I flew long haul before without any issues. This lasted about 2-3 years, every bump was enough to set it off.

But out of nowhere, since last year it doesn't happen anymore, I can fly again without much worry, even sleep again during flights.

Not sure what caused it, or how I got over it.