You could try clonazepam to ease the anxiety. Take one one or two mg tablet after boarding the plane. Whatever you do, don't take it and then drive to the airport. I've been using it for years and it has been very helpful. I'm still wondering if what you are experiencing is Social Affective Disorder. It would be worth an hour or two of your time to see a professional to determine the root cause. (My doc is now recommending Lunesta for sleep and they all recommend Ambien, but it has to impact on me personally). Good luck!! You really must see these places. Flying Business or First may also help as there is much less stimuli.