put her in charge of the color sceme of the rooms and stuff and say you are in charge of putting the house together
Look on the bright side - when the house is done then wifey wants to have kiddies, you'll get even LESS sleep ... 
we moved into our house and my mothers boyfriend stated "new house, new baby" i looked at him and fell over laughing, i said ohhhhh noooo! no more babies, we moved in our house in April 2001 and in June I found out I was pregnant with our son, I still tease my moms boyfriend and say he cursed us...lol...
after my son was born, I definatly took care of the "no more babies problem" with a lil surgery called tied tubes