I think God's best is that a man a woman stay married for ever -- until death do us part. However, we are dealing with flawed human beings and because of that there are valid reasons for divorce.
Just for the sake of argument:
Can anybody find a valid reason as to why a woman been beaten (not once but several times) by her husband to an extent to be sent to the hospital (not once, but several times) should not file for a divorce?
Can anybody find a valid reason for not divorcing a husband throwing acid at a wife's face and disfiguring her, and blinding her because of it?
Can anybody find a valid reason for not divorcing a husband that the wife knows is violating his own daughter(s) and also his only son?
I cannot find a valid reason for not divorcing in the examples above or many others that could be provided. IT WOULD BE IMMORAL NOT TO DIVORCE in these cases.
WHAT I FIND IMMORAL are the trivial marriages that produce trivial divorces. The ones that after a few hours, a few days, a few months, the ones with 'irreconcilable differences.' That's what is immoral. There is nothing that God cannot do to fix a marriage that has 'differences.' 'Differences' can be reconcilable.
Marriage is a serious thing, however, in this day and age, it is taken too lightly.
The "I", "me", and "myself" are furiously working and cannot see anybody else in its path. "I", "me", and "myself" do not like the way he/she looks in the morning. "I", "me", and "myself" cannot stand he/she did not lift/dropped the toilet seat. Well, that's irreconcilable differences and "I", "me", and "myself" want a divorce.