That's so very sad. But you did all you could, and you got her off the streets and you really tried. That had to be frustrating to bring her in and then not be able to take her back when you realized you couldn't be notified. There's still a chance though that her owners will be looking for her and will call the shelter.

You're always doing everything you can to help the unfortunate animals you run across, and I think that is a wonderful thing. *hugs*