have you asked your wife what her definition of a "husband" is? that term might not have any sexual meaning to her at all. she might just mean she needs someone she feels is able to be there for her and if you get too wrapped up in your own issues you might lose that ability. i'm not saying that's what she means, but you should ask her what a husband is to her.

as for "outing" yourself to her, what is it that you hope to gain by doing that? in your ideal world, what is it that you would want your wife to do with this information? is this something you really *need* her to know in order to maintain or improve your relationship with her, or are you feeling a urge to tell her because you feel guilty keeping a secret like this from her?

you say you don't want your relationship to change, but revealing this information to her will almost certainly result in some sort of change. not necessarily bad--but there will be change.

i really apologize if my response is a downer--it certainly isn't meant to be!