NOTHING is lonelier than living with an active alcoholic. You could have better company if you were a hermit living in a cave at the top of a mountain.
And you do NOT want to have children with an active alcoholic. You can adopt children if your bio-clock runs out, you can volunteer with kids, you can have a great life. But not with an active alcoholic.
In four years you will be forty. Do you want to be stuck with a toddler or two and trying to negotiate a divorce, or, worse yet, trying to raise children with someone whose condition is likely to deteriorate further?
You are still a young woman (geeze, wish I was still 36)--the sooner you leave, the sooner your new life begins. I only say this because you mention that you were thinking about leaving already. A little fear and loneliness in the beginning beats a lifetime of it.