It was good that you brought the issue to her attention and I think it would have been nice if she'd thanked you. I wonder if the lack of thanks might not be such a big deal if you didn't have other issues with her right now.

I probably would've googled the other people, too. I guess maybe it's snooping--like if she left an address book lying open where you could see it, you'd know it was probably not meant for you to see, so the "right thing" would be to ignore it. But I don't think you did anything terrible at all.