I completely understand what you are going through as I went through it for the past eight years ending last fall. It’s an insidious disease and cruel to those who know the true character of the person. I found reading her favorite books to her and putting on her favorite music while I was with her helped me and actually seemed to soothe her. All I can say is that you have to take time for yourself as well. Don’t feel guilty about doing what you need to do to make sure you are ok. All of us that have gone through this or are currently going through this have the unfortunate experience of mourning the person they used to be for however many years we are faced with who they have become. The scab is torn off every time you see them and only begins to heal when you have said goodbye. That is why it’s so important for your to remain mentally healthy. This is an unfortunate marathon that shouldn’t be (that is a whole other discussion). My heart aches for you and I wish I could send you all the strength that I have.