As I said in my previous post, you have to do what you can live with.
What you have outlined is a life of misery for yourself to take care of an adult child that does not care about you.
A hard truth to keep in mind is that you will not be here forever. What happens then? Here's how I look at it, by paying for his housing whether it's an apt. or motel room, you are prolonging the inevitable. At some point he will have to deal with his life on his own.
Your family is concerned for your well being and health.
There is a reason the flight attendant tells us to put on our own oxygen mask first before assisting a child. If you don't, you could pass out before you would be able to assist the child.
You need to put yourself first. You need to take care of you.
I think you have your answer here. It would be one thing if he expressed that he wanted to work on getting help or was willing to take his medications but he's not.
You know your son, you know how this will play out. I know how much your heart is breaking from all of this, I've been there. All who are here have been there.
I'm so sorry you are having to deal with this.
This journey we are on is not an easy one but you are not alone.
The best thing you can do is to take care of yourself.