Hi, I am not MIFLAW and have nothing like his wisdom or his years of experience.
I am however an alcoholic.
Nifty, you have done absoloutley the right thing for you, and for your dc. Being an alcoholic makes me totally selfish and gripped by the need to have a drink, and when I have one, the inability to stop myself. It renders me not-responsable for myself, let alone any other person.
I am not drinking now, and that is because I recognised the state I had got to, and knew that I had to do something about it. Before I was at that state, I knew and acknowledged that I was an alcoholic, but that only explained my drinking, it didn't make me want to stop. Nothing that anyone round about me had said had made me want to change, it only made me hide from them. I needed to get to that place on my own to have enough motivation face my addiction and stop drinking.
Many, many alcoholics don't get to that realisation and the desire to change until they reach rock bottom. Perhaps by making your dh leave, you will have given him the kick that he needs to recognise his rock bottom. Some people's rock bottom is lower than that, they may end up in prison or hospital. But the important thing is that none of that is your responsibility or fault, nifty. Partners / wives / husbands / do more damage by enabling the addict.
You might want to think about contacting al-anon for families of addicts. You will find people there who have been through the same experience as you, and if your dh chooses to stop drinking, al-anon could be a useful ongoing support for you, even though he may not be living in your home.
Reading this thread makes me feel ashamed of myself, it is hard to see the way drinking hurts the other members of a family. I wish you all the best nifty.