Why the Wife?

I watched a few seconds of the press conference at which Eliot Spitzer resigned. There's something I don't understand: why was his wife there, besides him? Given the circumstances, wouldn't she have preferred to stay home? What is it with politicians insisting that their wives be there in this moment of public humiliation? After all, it's not like there are any doubts and she's standing there to show support for some baseless accusations, right? I can't figure it out.