Hi Littlestar and a warm welcome.
I've been in exactly the same situation you're in right now. When I moved in with my partner I knew he liked his wine but boy, I had NO idea he was an alcoholic. It's very distressing and confusing.
None of us here would ever tell you whether to stay or whether to leave. You seem to understand that you can't stop him doing what he does - you're doing a lot better than I did for a long time! I think it might be helpful to ask yourself some questions - How do you feel about what your life is like now? How long do you want to live like this? How much can you take? Do you have some boundaries that you can use to help you decide what to do?
When I first realised that I was living with an alcoholic, it was a very scary moment. I began to find out all I could about alcoholism and alcoholics and read about Al-Anon in a book about alcoholism so I went to a meeting...and then another and then another. Those meetings, reading the literature, learning about the steps and reading this forum has helped me a lot in the decision I've made. I can only take it one day at a time at this point. If you stay today, you're not committed to stay for a lifetime, so give yourself some time and space and if you find a decision hard to make, well, you don't have to make one just yet.
Be good to yourself
HugZ
Sandra