You touched on something that I have wondered about: how universal is "body language"? It's my experience that there are significant differences in interpretation of body signals between East and West. It's not something that I would rely on to judge my chances!
I can only echo Kristleh's advice: talk to her without trying to come on strong... and take your time... Maybe she has no-one else but said that to avoid hurting your feelings? Who knows? Could you not try inviting her out again, but as part of a foursome in a situation where she would feel comfortable and safe?
Ivor and Mel
