"Do you care to comment more in depth on personality changes as people approach death? You spoke of how we all wear faces; I assume that as the effort and intensity involved in approaching death increases, a person loses the desire and or energy to maintain a "public face." You also spoke about how sometimes what we see at the end of life is not the true person, but a disease-distorted self. How do we know which is which? And does it matter? Should we just write off all unpleasant personality changes as the consequence of the diseases (medications)?"
I think the key to addressing the above questions is realizing that we die the way we have lived. The personality doesn't change, it intensifies, so if we were a "game player (and we all are, its just a matter of degree)" then we will continue playing the games we are familiar with---denial, little girl, macho man, victim, aggressor, controller, etc. As we begin to withdraw from the world around us, on the continuum of gradual death, we have less energy to interact with others and we care less about what is happening (what people are saying, thinking, and doing), so the games decrease. There just isn't the desire to communicate with others. The life work has gone inward so there is less concern about what is occurring outward.
As far as what I think we should "write off?"----All of it. Now is the time to put judgements and expectations aside and be in the moment. A person we care about is leaving this world. What they are experiencing is how they are leaving. They are doing it in their own unique way just as they lived their life in their own unique way. This is their final experience in the adventure we call life. Our role (whoever is present during this final journey whether it is family, friends, or health care professionals) is first of all, to see that they are free of physical pain (if pain has been a part of the disease process, keep medicating, if not a part of the disease process, then pain is not likely to be present as death approaches). This includes making sure that they are in a clean dry bed and safe from physical harm (falling out of bed or otherwise hurting themselves). We get to use this opportunity to express our love and appreciation. It is time to say our goodbyes.
People with unpleasant personalities while living will still have unpleasant personalities while dying. It is just that the closer to death they get, the less energy they will have to express themselves. You won't change them now. In fact, now, in the months before death, we need to let go of all those things we wish we had or thought we needed in our relationship from our mother, father, husband or wife, children (whoever it is that we are dealing with losing), but didn't get. It is too late. The person who is dying doesn't have the energy or the inclination to address those issues. At this time I recommend we give what it is that we wanted. Turn the tables and give what you didn't get but still need. Generally, it is love and attention that we want so desperately and find so lacking. Actually, a person doesn't have to be dying for you to try this. Give what you want. It might surprise you.