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For starters, you didn't screw up. It sounds like you invested in a much more sensible manner than did your husband, given that you have 25+ years until retirement. Don't feel guilty here; you have done the right thing and, whether you know it or not, you probably still are doing the right thing by staying invested. The returns from a diversified portfolio will, in time, beat your husband's much more conservative allocation. And time is on your side here--you don't need the money for 25 years. I know it is hard to believe, given how painful the current market environment is, but there have been periods like this before. The market will recover sooner or later, and if you sell your investments now you'll miss out on that.
As you approach retiremnt you should rotate into more conservative investments to preserve capital, but with 25 years to go, taking some risk is the way to go. Time is on your side.
Cary is right though; it is worth spending the time (and perhaps a bit of money) to talk with a financial planner to make sure that both of you understand what you are holding. If nothing else it will make you feel better!