Christian leaders seem to worry that allowing any divorce is to open the flood gates to every divorce.
The idea is permitting divorce necessarily means taking a disposable stance towards the covenant of marriage. This is just not so.
God does not take marriage lightly, and He is described in the Bible as divorcing Israel:
And I saw, when for all the causes whereby backsliding Israel committed adultery I had put her away, and given her a bill of divorce…
-Jeremiah 3:8a, KJV
If treating the marriage covenant as disposable is the real concern, one’s ire ought to be directed at those behaving thus–i.e. cheaters.
They have decided by their adulterous actions that the requirements of marriage–namely, to be sexually faithful to one’s spouse–is disposable based on how one feels or what one wants.