Hi walktheline,
I, too, am a nervous flyer, always flew on a cocktail of mind-numbers (usually alcohol plus xanax) and was absolutely terrified the first time I had to get on a plane without my crutches. Like visibly-vibrating-terrified. You know what really really helped, though? Breathing techniques. Specifically, alternate nostril breathing (pranayama). Check this out, for a list of benefits, and, if you scroll down, instructions on how to do it:
12 Great Reasons To Start Alternate Nostril Breathing: | Rejuvenation Lounge
I sat down, closed my eyes and practiced this technique the entire time I was waiting for the plane to get going and through the entire takeoff until the seatbelt sign had gone off again (the most terrifying part of any flight for me). It worked wonders.
The instructions here don't tell you how long to breathe, but I relied on the memory of an old yoga class and did an inhale in one nostril for a slow count of 8, held my breath for a slow count of 4, and exhaled for a slow count of 16. The counting also helped a lot: you can't help but calm/quiet your mind when you absorb it with a task like that. I was the calmest I'd ever been for a flight (though it took a while for the terror to abate). During the flight, try to concentrate only on staying in the moment and keeping yourself calm. Don't think ahead to any emotional scenes with your girlfriend. Address each fear in its own time. The breathing/counting really, really helps.
I'm fifteen months sober now and I still use this technique every time I fly. I'm still a nervous flyer, and I still dislike takeoff, but I certainly don't need alcohol to get me through it any more. And every time I fly successfully, it adds another positive memory and another piece of sure knowledge that I can do this.
Good luck with your girlfriend also - hope it goes as well as it can go.
xx
Zini