What kind of free public istance and support is there for traumatic brain injury victims?

Hi, I am concerned about my mother. She is 53, I am 23, and I have a 17 year old sister. About 7 years ago my mom had a brain aneurysm which almost killed her. After months of surgeries, time in the ICU, and rehabilitation she was able to get back on her feet for the most part, even though she's never really been the same. Sadly, over the past 6 months or so, my mom's health has seriously deteriorated. She had a small stroke that went undetected for awhile, and has since lost her job due to inability to perform. She is barely able to function in the sense that she can't get herself to do anything, feels physically ill often, and has erratic behaviors and emotions. She can't seem to even get herself to the doctor on her own as she lacks any organizational skills or motivation anymore, and also has trouble communicating effectively. My mother is divorced and any extended family we have lives on the East Coast. I am completely at a loss as to what to do to help her anymore as the problem has become bigger than I or my sister can handle on her own. Where should I go for help? I don't think my mom can survive much longer like this...physically, financially, or mentally. I am in Orange County, California. Does anyone know of any free programs that could help her or any suggestions as to who could provide her with some guidance? I don't even know where to begin, and she's barely able to take care of herself anymore. If anyone has been in a similar situation or has experience with this, any suggestions would be appreciated.