My alcoholic friend tried some harm-reduction / drinking in moderation approaches, and while these approaches might be worthwhile for some people struggling with alcohol, I wasn't comfortable with them at all. I know that my "discomfort" was my problem and not the alcoholic's, but just like you I was just so tired of all the drama alcohol caused in this friendship.
Agreeing with what the others said (know your boundaries and time will tell)and saying sorry and I can relate.