Hi SWest
I'm so sorry you are having this problem with your son. None of us here have yet come up with an answer to this situation, but as Nan said, some of us have grouped together to try to make the authorities aware that this problem exists - the sweet, rational, believable psychopath playing havoc with the life of a child, driving the 'normal' parent to the point of despair and hysteria. There are just a few things from our collective experience that may help you:
1. Continue to believe in yourself. You are NOT mad, you are not imagining any of this, you are a caring parent and your son needs you in his life.
2. Document everything. Keep a journal of times, dates, places, events. It is easy to become flustered and forget the main issues in the haze of lies and confusion created by the psychopath.
3. Have a look at this site re Parental Alienation:
http://www.couplescompany.com/Advice/Parenting/PAS2.htm
4. This woman knows exactly which buttons to push to make you appear hysterical, neurotic and over-emotional. Somehow you have to overcome this and present the appearance to the authorities of being rational, sensible and stable. Sometimes its easier to do this in writing rather than in person.
Not sure if any of that will help, but please come back to this site often and offload - I have found that just being able to communicate with people who understand the situation is a huge help in healing and taking charge of your life.
All the very best
**edited to make link clickable, Di