What do you think will break her more... the flight or loosing the only family she's known for 8yrs??
go to your vet and seek advice. If she is healthy then she will fly fine. I know 3 dogs all elderly that made the trip from Paris, to canada, then to australia all in one big long flight... 2 drink stops and they are fine.
As heartbreaking as it is for you, the dog will suffer more. Perhaps even die due to not eating through missing her family
And please don't just leave her with anyone AND never advertise her as 'free to good home'
There are people out there that will grab dogs that are FTGH and use them to train thier dogs to fight.