MG - Stop beating yourself up here.
The way he has been behaving, it may have been quite some time before you could have had one of those quiet sane conversations.
I am convinced that a crisis would have happened anyway. He was already out of control with his disease and with the girlfriend
and you cannot deal logically with a person who is totally out of control. Your daughter could not deal with him and neither could you.
As sad as it is, this is HIS disease and nobody can be safe around a person in the shape that he is in right now. He is not even safe with himself right now.
You did the right thing. It was very brave and it was the right thing to do. He is now under supervised care where they can help him get through this. You could not have offered the same care yourself.
You are a wonderful person with a wonderful son who is out of control. Just keep praying and let the answers come.
Love you.