S.M.
People drink for many reasons and I agree with Catherine that the only person your friend can help is herself. I once had a stressful job because of a terrible supervisor and it seems just about everyone at that job drank after work days, so eventually I drank after work like they did. I caught myself going down the wrong road of coping with alcohol when I would end my work shift, by daydreaming of what I would drink upon getting home. I don't think that made me an alcoholic, but I didn't like that I was looking forward to drinking without an ocassion/reason. I told myself that I would only drink for a special ocassion or socially with friends, but not to cope with a lousy boss.
The reason I am sharing this is because your friend's husband may have his reasons to 'relax' with beer. Communication is so crucial in a successful relationship and if your friend comes across as judgemental (as she probably already has), he may never open up to her. If she is concerned she should say what she feels when she sees him drinking, but speak only of what she feels when he drinks, not that he is an alcoholic because he drinks. Good luck to your friend.