Hello,
I just finished reading your story and the good replies you received, so I only would like to make a few suggestions......first now is the time to set your boundaries and no contact on your part would help you to deal and heal in the quiet, without the drama....second, please document everything.....record phone calls, save text messages or emails, make a journal with dates, times, etc. about her abuse (for example at your mom's house), include the times when her daughter was subjected to this behavior, also any arrests, treatment, etc......if CPS is indeed looking at her (and that would be a good thing), since your have been present for the last few years, they may very well call on you for verification, so do what you need to do to protect you and your son, documentation, documentation, documentation.....addicts can be very irrational and violent when they feel their control and meal ticket (sorry) slipping away......
The quality of our life is not dependent on the circumstances we encounter. The quality of our life is dependent on what we learn from the circumstances we encounter.
Peace,