When we express extreme anguish over a spouse's disappointing or even bad behavior, the underling belief we have—which we don't know that we have—is that our personal anguish will somehow touch the other person. However, if the person lacks the ability to have empathy (a clinical condition; can't conjure it up, can't imagine it, lacks the ability to produce it) we have to look at that condition as if a piece of that other person’s DNA is missing, and change our own behaviors in relation to that immovable situation. It is like dealing with any other handicap in any other person: the person can't walk because they can’t. They are in a wheelchair. Likewise, we must view this emotional disorder as a mental wheelchair.
Our illusion is that if we could just explain it better, if he were to read the right material or get under the influence of the right person, this could be fixed. Chances are that these hopes are ill-founded if it wasn't fixed after reading the first book or having the first discussion. Habit can clobber sane rationality/courage any day, if we one is dealing with a lifetime chronic situation.
Therefore, when we personally have anguish we need to come to see that we are wasting our own emotional capital, only ruining our own day. It wears us out, but does nothing to the other person. He may be having a fine day—oblivious to us. When we figure out that this is in fact the dynamic we are living with, our wise, better course would be to conserve our own emotional energy via self-talk that goes something like this: "This isn't fazing him a bit, so why should it faze me?" and get busy doing something very engaging that you love to do on your own. Simply learn to unhook from the cause of the devastation. Don't GO there. If HE is not feeling anything, why should YOU be? If you remain a victim of chronic dashed expectations, you will forever be miserable. If someone's devious or underhanded behavior always takes our breath away, we will always be reeling. If, on the other hand, we note the underhanded behavior and unhook, check-out, and expect it, then we can move past it and have a life of our own.
It might be quite life-giving to learn how to live in the moment better. When things are going well, act like the big picture is good. Pretend. For your own sake, enjoy all of the gusto you can get out of the relationship while it is going well. It would be similar to relating to someone who has periodic memory loss and doesn't even know who you are. You would simply learn to relate to him (or her) fully for those moments when his memory returns and he does know who you are. Aim to obtain from the relationship your own momentary joys—and unhook from the rest. Die to any and all expectations that it will ever be otherwise. Live a life beside him for all of those moments when it is obvious that he is not in the relationship and doesn't have a clue about how to get there. Carve out of life your own quiet joys next to him. This will revive your own emotional reserves and give you zest for living life wherever there is life—with other relationships and pursuits, for example. And of course you always have a secret cathedraled life with God that you can retreat to for the most trustworthy, satisfying nurture a human being could ever want. Go there and mental healing will ever flow.
Remember that the goal of this life is not personal happiness. It is wanting to be conformed to the image of Christ, no matter what it takes. It is submitting to whatever surgery is necessary to take on yet more of His nature. We have this promise: "When we see Him, we shall be like Him" (1 John 3:2). Saddle up.