Hip replacement is no excuse but it sounds like it is what caused his relapse. As you know life is going to throw you very tough challenges no matter what. That is no excuse go go back to using. You have to learn how to live life on life's terms and make the right choice when confronted with a challenge. I have a hard time with this. I would not kick him out after just this one incident but let him know you are serious, you love him, but drinking while In your house will not be tolerated.