Note that in the Catholic Church, as in the Orthodox Church, "marriage is the mysterious or mystical union of a man and woman - in imitation of Christ and the Church -"
It's more than a contract. But in the Catholic Church, it's never less than a contract. The Catholic Church respects people enough to respect their vow: "til death do you part."
I think you're misunderstaning.
The Orthodox phrase it as a capitulation but not as one that the church innovated; THEY THINK CHRIST OFFERED A CAPITULATION IN MAT. 18:18.
No divorces can take place in the Orthodox church unless they fall into porneia; the only difference is the Orthodox feel that even then it is as a capitualtion NOT that marriage didn't exist.
The reason behind this is the Orthodox do not feel the wedding CREATES the marriage. The Orthodox bless an existing marriage.
There is a difference in reasoning, but the effect and the rules for remarriage are the same.