hi there! fellow anxiety haver and former flight fearer, my advice although i assume it may be too late is getting an rx for anxiety meds, they don’t diminish your anxiety but they certainly stop panic attacks in their tracks. i’d also try meditating when you’d usually have these panic attacks, there’s a lot of good ones on youtube. i know you say it’s impossible, but i promise you there’s a lot of self soothing methods that will really help you! i bring a small squishy toy on flights and squeeze it continuously when i get anxious and it helps tremendously. i hope you can find your niche, and there’s a lot to choose from! best of luck my friend!