Book excerpt: HARD COVER EDITION------WHAT'S IT LIKE to be the only son of a widowed mother who is rapidly sinking into the opaque fog of dementia, and who lives alone half a continent away? ROBERT TELL tells this tale with compassion and humor. DEMENTIA DIARY reads like fiction and covers the fifteen year period from his father's shocking death in a department store to his mother's 92nd birthday. It is meant to be a portable support group. If you have watched helplessly as your parent, spouse or friend's identity disappeared into the sinkhole of Alzheimer's Disease (or another dementia), this heart-wrenching memoir will touch you deeply