There are many reason how the hardness of the heart lead to divorce. There is anger towards the wife or husband, unlawyalty but the one that is stated is in the Bible is lust which I consider most divorced partner have encountered. It is not only men but also women so the devil is in work you must be prepared with a verse in the Bilble. For example memorize a verse or two like "greater is he who is me than you who is in this world" or " get away from me satan". So one must be prepared at all times not only from temptation but also when GOD call us..