In the Gospel of Matthew, Our Lord makes it very clear that "what God has joined, let no man rent asunder [i.e., tear apart]. In other words, man and woman upon marrying become a fabric. They are interwoven together like threads in a garment. And Our Saviour says the only reason to part is for "unchastity," from the Greek porneia, which is either taken to mean serious sexual unchastity or, as the Catholic Church has historically defined it, that the marriage was never valid in the first place.
Now Rev. Pat Robertson is saying you can divorce your spouse if he or she has Alzheimer's. What about "for better, for worse, for richer, for poorer, in sickness and in health, forsaking all others"? How is the sola scriptura (i.e., the Bible as the sole rule of faith) authorized to overturn two millenia of Christian teaching? Where does he find this in Tradition or Scripture?
As depressing and disappointing as this is, I think it clearly shows what happens when we become a magisterium unto ourselves or reject the Church's legitimate magisterium. Eventually, traditional doctrine will slough off to become a religion made in the image of man and not a reflection of the one, true, triune God.
Please pray for this man's return to orthodoxy.