Why Does the Cheated on Spouse Always Attend the Press Conferences?

Governor Spitzer's Poor Wife.

Why is it every time we see a politician or celebrity who has been caught in the act, they always make their poor wives join them in a press conference?

I get the idea that perhaps someone might not be willing to throw away a marriage do to an affair. But honestly, do they have to attend the public press conference? All I know if it was me, I would tell my spouse, you did this on your own, you can face the press on your own. Have fun. Seriously hasn't that poor woman been humilated enough...