As you can read here in many many posts, getting out of a live-in situation, whether married, or not, with an A is hard, beyond hard, and very painful.
Take your time, hold on to your peace and serenity with all your might. You have no idea at this time what you would be getting yourself and your child into.
He should be clean and sober, and living on his own, and a productive member of society (whether working, or volunteering or going to school, whatever it is) for a long period of time before you even think of moving in together.
I moved in with my ex abf after 3 1/2 years of an amazing love affair. It only took four months for me to be out on my A** with my clothes in garbage bags, and no place to live. I had no idea until we lived under the same roof what alcoholism could do to not only the alcoholic but everyone close to them.
Wait...Wait...and then Wait some more. If it is meant to be, it will be. More will be revealed....