Actually, how she found the email was the last thing on my mind. She must have access to his account which means, he likely gave her the password, so why shouldn't she go have a look?
That's her version, that he gave her his password, perhaps he did but that doesn't entitle her to look into his private stuff. I doubt that any man (or woman) really likes to have their mail looked at.
As to "why shouldnt she go have a look", well, I can remind you of that comment which is only too true. A woman 'feels' that everything a man has is hers also, but anything a woman has is only hers. You qualify with this version of 'women's logic'.