I would definitely talk to a lawyer before you do anything. Moving out may have some impact on your ability to get the house back. You also need to protect your child. FWIW, you want to file first and gain temporary custody. Keep documentation, including the rehab stint that you mention above. I would be incredibly surprised if a judge would allow 50/50 custody to someone who went to rehab but is not actively seeking treatment.
A lawyer can tell you what is required to protect you and your child. Do not listen to his quacking. BTDT. Sounds just like my STBXAH. He talked about keeping the kids, keeping the house, and now 4 months later, I'm having to "remind" him that his very young children need to see him over going to practice with his band. :chatter
Blah, blah, blah. Keep on the path that is best for you.