Honestly having married into "alcoholism' and having it around as a third party for my daughter's childhood, I would not continue in the relationship. Maybe he will recover and be sober, but you won't know that for a loooooooooong time yet.
If you stay, be honest about the gamble you are taking so that when you marry and have a child you aren't too disappointed when your entire home life and all your dreams for your family are subverted by alcoholism's agenda.
V