Can I add something I don't mean to be unkind about.
If you are travelling F on a direct flight, why would your wife be unfit to fly?
If she needs hospital treatment, then I can see unfit to fly.
If she is going to lie down in a bed in a dark room and try and rest, then maybe F on a 12 hour flight is not that bad a thing?
If you were in economy, or even some CW seats, then I could understand.
But I would be OK with the flight, and splurge on a spacious, comfortable transfers to and from the airports to make life easy. Maybe even wheelchair?