When we choose to stay married to an addict, unfortunately we also choose to accept this very real possibility. If its not something we are willing to accept, then we must remove ourselves from the situation. I think you already know the answer to this one....
How old is your son? Are you willing to take the chance of him possibly finding his father before you do? I'm sorry you are hurting so badly. I wish I could give you the answers, I wish someone had the answers for me.( I am also still married to and living with my AH. ) Hang on there, and take care of YOU and that precious BABY. :ghug3