My children are useless. What should I do?

Solution 1:

I loved the game! You should include links for the game so others can find out more about it.

Anyway, the answer:

SHIFT + ` 
clearwife

--via GameFAQs

You can read more on the GameFAQs cheat page.

Your friend was correct about that being the only option in-game.

Solution 2:

Remember that if you get to level 3 of the selling skill (which gives 100% of the item's value when selling it), you can just buy whatever you like, divorce her, and then sell what you bought for the full amount you spent. So what you buy doesn't have to be sensible.

That's what I did - bought items and spell scrolls until I got practically nothing left, divorced her, then sold it all back. 50% of nothing is nothing. Just remember to remove all items from her slots first, otherwise she will take those away with her when she goes.