I dealt with depression since my teen years too and I ended up self-medicating with alcohol. Ultimately, I had to get medication that helped me before I was able to stop drinking. For me, the medication levels the playing field and gives me a chance.
Be cautious with your thoughts that you might not be an alcoholic. You might be right, but denial is a huge part of alcoholism, and it's also a fact that alcoholism is progressive and will get worse unless you stop drinking.