I spent some time re-reading the Scriptures regarding marriage and divorce that are listed in my Marriage/Divorce links.
One thing I noticed was that the concept "one flesh" was mentioned in Genesis, Malachi, Matthew and Mark.
In Matthew and Mark, Jesus says "What God has joined together, let not man separate."
In Mark and Luke, Jesus says "Anyone who divorces his wife and marries another woman commits adultery against her." It is only in Matthew that Jesus mentions an exception for adultery.
Paul appears to reaffirm this concept when he says "To the married I give this command (not I, but the Lord): A wife must not separate from her husband, but if she does, she must remain unmarried or else be reconciled to her husband, and a husband must not divorce his wife."
Only Paul addresses the issue of a marriage between Christian and non-Christian. He says that if a believer is married to an unbeliever and the unbeliever is willing to stay, the believer must not divorce.
David Reagan's ministry (http://www.lamblion.com/) focuses on the end time prophecy, made this comment once about biblical interpretation, "If the plain sense, makes sense, then don't look for any other sense or you will wind up with nonsense." I have always found that helpful as I think about Scripture.
So what does the plain sense of all this seem to be?
a. Marriage is a one-flesh relationship that God created and man is not to destroy it.
b. If both partners in marriage are Christian, then adultery is the only clear grounds for a divorce with the possibility for remarriage without committing adultery. This needs to be even looked at further since it was only mentioned in Matthew. It is puzzling why it was only mentioned in Matthew. Also, it does not say that in cases of adultery you have to divorce.
c. If Christians divorce for any reason other than adultery then remarry, they are committing adultery.
d. If only one party is a Christian, everything still applies as above, unless the non-Christian leaves.
So it would appear that all of these reasons I so commonly hear for divorce, such as irreconcilable differences, incompatibity, we should have never have gotten married, we don't love one another anymore, my spouse has emotional problems, and others, are not valid reasons to get divorced.