I told him that it appeared that alcohol came before his family and that it was more important to him so that feels like someone cheating on you because alcohol has replaced you in importance
Bingo! That is the nature of alcoholism. Nothing comes between an alcoholic and his/her booze. It is higher power, God, love of life, necessary like air. And if you plan to live peacefully with an active alcoholic you must accept this as part of who they are. It's a good reality check because there is nothing you can say or do that will change an alcoholic.