It doesn't matter what your friend thinks you can do, it matters what you think you can do. Or not do.
Before I understood alcoholism and alcohol abuse I used to think of other people "oh, they can have ONE, one won't kill you." It was only when I learned about alcoholism and admitted that I was an alcoholic that I realized that one will kill you. And I can never only have one. If I were to decide to pick up a drink right now, it certainly isn't going to be to have just one.
I would be hesitant to follow the advice of a perhaps well meaning friend on this issue. Only you know truly what happens when you drink. You wouldn't be here if alcohol were not causing trouble in your life. Would you really want to risk experimenting whether you can achieve moderation?