I assume you have tried attaching the file to an email. If you haven't, start there. Write an email and drag the file into the body of the email.
If that does't work, it is probably because it is too large. You could upload it to youtube (private or public) or drop it in the public folder in
Dropbox and send her the link to download it.
As for Facebook, I assume there is some sort of video app, or you could use, or do the youtube thing.