Heike, being a caregiver myself, I know that the worry and the frustration wear one down even more than the physical tasks. It is the mental anguish that makes you feel tired and isolated because no one else seems to understand the whole picture. Do set aside a few minutes every day when you shut off the thoughts of illness and caregiving. When you are taking that walk around the block, look at the buildings, the people and make up background stories about them to take your mind off the troubles at home. You have to look after yourself, you still have a life to lead.