From personal experience I do keep an eye one the crew. When the engines spool down suddenly after a climb out, or we hit a bumpy patch, I glance at the cabin crew in their jump seats, and if they're still chatting among themselves normally I know there's nothing to worry about.

Still, I wouldn't like to be on tenterhooks for seven hours so I would vote for the flying with confidence course, and I'd even vote for the valium (it won't "zombify" her but it'll certainly take the edge off).

And not that it helps, but even cabin crew get scared of flying sometimes. It's a professional hazard and they get 'treatment' in exactly the same way as your friend.