That's why this is so unfair. We worry about these WAW's finacially but believe me they'll be just fine. You will have the day to day expenses of your girls, and that will only get more expensive as they get older. Make sure that you keep your emotions out of this because the one thing that I do know is that he will never have the expenses that you do and the ones that will suffer if you don't get enough are your babies!
This was his choice. Let him figure it out for himself!