Welcome! There is a lot of good information in the 'stickies' section. I found al-anon a great comfort. It helped me keep a sense of calm--sometimes--in the midst of my ex's alcoholism.
And remember, you don't have to make any decisions until YOU are ready. Every family is different, but I am a fan of getting good information. Whether it is from SR, al-anon, a therapist, a lawyer--all of these people can give you the information YOU need to make YOUR decision. Going to see a lawyer is sometimes free, and can be a helpful first step. Same with a financial planner, or career counselor.
Separating, staying, divorcing--we make choices that feel final, but anything can happen. I know people who have divorced over alcoholism, then remarried a few years later! And people who live in serenity with a loved one who is an alcoholic.
None of your choices is easy, but take the time you need, and welcome!!! I wish all the best for you and your family!