What I'm wondering is, why don't you feel comfortable enough with him talking about what your concerns are? That would be my first suggestion. You have some serious concerns about a serious issue. So before you even talk about anything else, I'd ask HIM about it. He won't tell you the full story but it will give you more information.
The part that you should focus on though is you and how you go into relationships. If you are going into any relationship, already requiring that there will be changes then the relationship is doomed. Add the alcoholism and not only is it unrealistic to expect he will 'change' for you but that you have that much control over anyone. Would you allow some guy to only enter into a relationship with you if he thought you needed to lose weight first or get boob implants? Doubtful.
At first when I read your posts I thought of a person who had some slight interest in a nice guy and was thinking about going out with him, but as soon as you mentioned how if he did things you didnt want or like that he'd have to change. That is when I realized that in general your perspective on relationships is more of the issue than what this guy is.
Yes I do think he is an alcoholic, probably a pretty severe one from what you say. There are more red flags than a bullfight with this guy but that isn't here nor there to me. You cannot change people. What you see going into a relationship, good or bad, is what you will experience for its duration unless the person themselves wants to change (this is esp true with alcoholics).
p.s. celebrities tend to have lots of money to afford constant stints in rehab, personal addiction specialists, attorney's to deal with legal issues, etc. Not very realistic to compare someone on a regular income able to 'overcome' things like some celebrity. Their stories are often the exception, not the rule.