Judith, is there any way you can get an afternoon off from everything? Go see a movie or meet a friend for lunch? It's so important to take care of YOU...or burnout/meltdown is inevitable.
Talking about those interminable hospital visits, reminded me when I was going to Mayo so much for blood work, scans, meetings with oncologists, etc. I told one of the volunteers I should just pitch a tent because I was there so much. I've also been in the role of caregiver, some years ago, when my b.f.'s mother who had terminal colon cancer came to live with us. It's extremely stressful. So please do try to get out and do something to take your mind off everything for a few hours! Otherwise, resentment is guaranteed.