Ahh, I think what you're looking at is a sort of "private message system"- and what we have here is a tad more simple. The software knows the email address, and gives you a form that will let you email to her email address without revealing what it is to you. So, with the system operating properly, unless you get an error message you can assume that it was sent.
There isn't any way to verify it was received- she could have an old email address, or her spam filter might see the email we sent as bulk mail. (our system has been flagged as a spam sender because of the quantity of registration emails we send out)
Best bet? Mention in a post you reply to an already existing thread that you'd like her to email you through your profile.