Despite everything you've just gone through, what I hear coming through loud and clear is your
compassion for your child who is suffering (and hurting others), and that's such a gift for him and for you.
Even though he may not acknowledge it, you having the strength to hold on to a boundary (rule for your own life) could possibly create some stability and predictability in your family system, that might benefit him. At minimum, it gives you a breather, because you are a limited human being who cannot possibly do everything. If you don't have the bandwidth for persons to live in your home without getting mental health treatment, then you just don't.
This is not an easy situation for any of you, and it takes strength to hold on to your choices so that you aren't undermining S23 by rescuing him. He will do the best he can in this moment, and likely has resources you don't know of, and will have a chance to choose some resources to help himself. And, when he knows better and has better skills, he'll have the chance to do better.
I hope he feels the compassion, love, and care coming from you, underneath everything. That can mean a lot.
