Walls Up! Glass dome surrounding you!
Your home is not an option, period. Your life and your home are sacred, and your safe place, and no matter what, your home is not available to anyone who does not respect you and your life in it. That is the one place where you are free to be YOU, and it is time for you to be free to be all that You Are.
Your NMother is grasping for help, and she knows that you are a kind soul, and she hopes that you will crumble. But, there is a big world out there, a wide variety of places for her, many long-term places both private and public (we had to move my NDad around three times because he could not be happy in any of them - and then he just stopped eating....and died - lost Control - but that was his choice, no guilt here...). Furthermore, you are not her only child, you just happen to be the only compassionate one.
So, (((Les))) that is my emotional response to your situation. Protect Yourself and your home....
~onlyme