Attending Alateen

Ever since I was able to start realizing my father's alcohol problem, I wanted to reach out for help. When I began using the internet I always came across alateen and have wanted to attend their meetings. Just recently, I attended my first alateen meeting and it felt good in a way. I felt relieved from a lot of the burden I have carried for so many years, yet I still felt out of place because it was so new to me. My ever loving supportive mother does not drink and is there for me but I know that I want to connect with others and share experiences. I have found it difficult to go back just because I get nervous when I have to talk in front of other people. It will take getting use to but can anyone share experiences or advice? My mother and brother know that I attended the meeting but my father does not as I feel that he will feel distance and neglect or try to acknowledge even more that he does not have an addiction problem. I want to tell him, but I am afraid of his reaction. I want to show to him that his drinking has affected others around him to the point where I want to reach out for further support. Should I tell?