I know you haven't met each others' families, but by chance do you have her parents' phone number? If you do, you might call them to let them know it might be a good idea to keep an eye on her tonight or at least check in? (they do sound rather reactionary, but still...). That's really the only other possible thing I can see. It is a hard position to be in BNLsMOM. When you say that you have done all you can do w/o overstepping your bounds, you know that this is true. You are a caring person and you *do* know that balance.
Best wishes on you all tonight...