She's just going to go there and see what happens? On her own or with a friend? No wonder you're in a state as her mum but I have to say I was the same at that age and the situations I got into... Looking back on it, I hope my dd doesn't do the same.
How about hunting around on the web for a bit, get some information together, places she can go if things go wrong, hospitals, English speaking activities etc? There must be a sizable expat community, so bound to be an English church community, for instance which is always a good place to ask for advice.
Being me, I would probably buy her a one-year return ticket so she could come back at the drop of a hat if things go wrong and look into health insurance. She can register with the embassy when she arrives, although I have never done this myself.
I think at 22 you'll have to rely on her using her common sense but being the clucky mother-hen type that I am, I would probably even go over with her and see her settled! My poor dd, she's only 5 though so I may loosen up a bit before she leaves the nest.