Hi Dayglo,
I am a sufferer too, but I agree with all that has been said in this thread. If you didn't go to your mother's I hope you do go out for a while, and take your son with you, as you both deserve some time away to recharge.
It is difficult to feel so torn for wanting to be there, knowing you are being manipulated, not sure they can help it or not, the fear of leaving, the fear of not leaving, trying to establish boundaries, trying to enforce boundaries, etc. In the end, you need to do what is best for you, because not to is to leave yourself open for becoming burned out, resentful, stressed to the point of illness, or just plain ready to walk away. (I am also a supporter of children with PTSD, depression, addiction, etc.).
The statement of "you first" is not selfish. It is a matter of survival, and being able to continue to be a husband, supporter, father, and just plain functioning human being.
Debbie