I'm so sorry this happened. I get the sense from some of the responses that it sounds like only greys do this, but believe me, this happens to owners of all breeds. I have a scar from a Springer Spaniel we adopted in 1977.
It may have something to do with inexperience, but many of us here have reported being bit, and in most cases we did something we knew we shouldn't do. I'm sure Faye will find a good home, the problem doesn't sound insurmountable, Faye and her new family will have some work to do but it can all work out in the right home under the right circumstances.
I hope you don't write off greys forever, I've not had to deal with space aggression only resource guarding, but our 2 current greys don't display any forms of aggression at all. We can pet them on their beds, lay with them on their beds, take high-value treats out of their mouth without incident, bend over them, hug them, etc. without any forms of aggression. Please note I don't necessarily do anything I've listed often, e.g. hug them or make them uncomfortable so that they would react.
If you want to know what not to do, it would take forever to list, but in general some greys do not like someone bending over top of them, be disturbed while sleeping and/or laying on their bed, or hugging. There are excellent books as well, Patricia McConnell's "The Other End of the Leash" is excellent and you can learn a lot about dog behaviour of any breed.