My wife insists on having the passwords to my online and e-mail services. This bothers me.
Marriage is all about mutuality.
While you're trusting her with your e-mail passwords, she's trusting you to be the kind of man who would use those tools in pure ways. You should be glad to offer this access to your wife, for your own protection if for no better reason. If there's something inappropriate being offered to me, I'm protected by this kind of transparency. Areas that are 'his only' or 'hers only' are counterproductive to open trust. At home I don't believe in locked drawers or areas that are only his or only hers.