That's why I said "almost always."
Such circumstances are some of the only just reasons for divorce, because they are both forms of sexual immorality.
Obviously, a husband and wife should, where possible, seek to resolve their issues peacefully. Divorce shouldn't be high on the list of options.
Abusive spouses should seek help, from the church, then professional help, and if those don't work, the justice system should step in (if caught) to punish the behavior through flogging, or the spouse should file for divorce on grounds of sexual immorality.
If however, the above DOES work then obviously, there would be no need for divorce, which would tear the family apart.
RE spouses:
Abusers should be flogged if caught, and divorced if it continues, and if it continues still, should be put to death. Cheaters, depending on how forgiving the spouse is, should be divorced or seek counseling, flogged if charges are brought. Drug addicts should be flogged, and if they don't abandon their addictions, divorced and put to death.
