Hello, partner. Say, have you ever been divorced?
I believe in trying to do whatever you can to save the marriage, but sometimes personalities clash and incompatibility results in divorce. 
So no more till death do us part. You marry someone, then your personalities clash and you are no longer compatible. Seems a cop out to me.
Well, to answer your first question, I have been married for 21 years and never divorced, but I agree with you, people often "cop out".
Marriage is hard. It takes a commitment to be happy and understanding of each other's needs. Giving up seems to be a lack of character in my opinion.
Divorce, in my opinion, if often more difficult that working on the marriage with alimony, child custody, child visitation, distribution of property...etc.