Except they can't.  They can't give total self-gift.  They can't say in honesty to God.."I am giving all that you - My God, My Creator - gave me to this other!

Can't be done.

And it's the same reason that contraception isn't total self-gift. 

Children are precisely the purpose of marriage.  It's to ensure the good of children.

Marriage in this sense is cooperatively self-gifting with God.

The marriage itself is not "closed in on itself" but instead it - the coupling of wills and the bodies - exists for the good of something outside of itself!

You need to clear out some defective ideas you have about the Catholic understanding of marriage.

And if you disagree with the Catholic understanding of marriage, why are you trying to force the Catholic Church to change its teaching? Why not just recommend the civil path to others?

As I said you believe in separating - in dividing between - these realities of sex, marriage, children, love. The Church doesn't.

I was earlier right.