Low fixed income; mom has dementia and I need to find her a place to live!

My mom is 71 years old and has moderate dementia. I have been her caregiver for the last 6 years. She was told she can no longer drive or cook almost 6 years ago. She is currently living with my sister and is very depressed and wants to move back to Texas. She is on a very low, fixed income with no other assets to speak of. She needs reminders for taking her pills nightly, eating, brushing teeth etc. She does fine on her own for the most part but needs to be around people. She has a small dog who is her lifelong companion. I am at a loss as to whether or not to find assisted living (which has proven to be ridiculously expensive and way out of our reach) or place her in a senior living community with home healthcare. However, I am completely unaware of how to handle this new dilemma I have. Any advice on what to do and where I can look would be very welcomed. I live in Richmond, TX so somewhere that isn't too far away would be great. I also want to know if there is any assistance that my mom would qualify for that I don't know about? Thank you so much!!!