There is a feeling, a sense, of relief at meetings from the people there. It's a respite for us all. We return to our homes with rational thinking about how alcoholism affects us and we live employing our new behaviors -- mainly no longer enabling the alcoholic -- and refusing to be abused. Like how we notice when a drunk sobers up...the drunk we love notice when we emotionally sober up.
One assurance to the alcoholic that can be made is that we are at meetings dealing with ourselves and not his/hers. Tell them we want to better ourselves...and his drinking/recovery is his responsibility. We must put ourselves and children first and ensure well-being for all.
At some point, we all reveal that we are attending Al-Anon...either by leaving our book on the night stand, letting it slip in conversation, or purposely planning on telling them.
I don't attend Al-Anon to force a person to quit or in to rehab. Telling the drunk that may also help. It's not about them.