Great that he has decided to have an appointment with a drug counselor. I encourage you to make an appointment with a counselor for yourself or attend an alanon meeting. I would love you to get stronger and learn to set firm boundaries for the kind of behavior you are going to accept in your life. Being part of someone elses addiction can make us as sick as the addicts. And just like the addict, we don't even realize we might need help.
I think having a plan is a key part in the personal journey loved ones of addict. Say he doesn't go to the appointment with the counselor what then? Do you have an escape plan if the abuse escalates (because once it happens once, it usually will happen again - only worse)?
My ex punched me in the face when I was 8 months pregnant. I lied to the doctor too - told her I smacked myself in the face with a broom handle. It was a turning point for me but still, to this day, I would probably defend him if asked. Codependents are just that way. He didn't mean it. Maybe I deserved it because I was being a bitch. He apologized. He was withdrawing and not in his right mind. And so on and so forth. The fact is, it happened and I needed to focus on the action and my response to his behavior. Not make excuses for his behavior. Hitting someone in the face or breaking their finger is NOT ok. No matter what the circumstances are. Addict never "mean" to hurt you. But they are selfish. They are only concerned with themselves and getting what they need.
Have an escape plan. Just in case. It never hurts to be prepared.
Learn how to set boundaries for yourself. Learn to enforce consequense for when someone violates them.
Take this seriously. Addiction is very serious. Accidently breaking your finger, no matter how you try to minimize it, is serious.
HUGS. We are here for you.