Alzheimer's Association Desert Southwest Chapter http://www.alz.org/about_us_about_us_.asp (602) 528-0545 or 1-800-272-3900 has all sorts of resources and varying programs. One is called CarePRO (Care Partners Reaching Out) "Developing the Skills Needed to Care for Someone with Dementia or Memory Loss," which seems like an excellent training session involving much support including attending five 2.5 hours workshops "to learn strategies to help them handle difficult caregiving situations, reduce caregiver stress, improve mood, and communicate better with others, including their loved one with memory problems." But they offer less intense support groups too, so prowl around the site and you'll see that Sun City has four options including one meeting at The Church of the Palms, etc.
