I can only imagine the frustrations you feel...especially since your children are exposed to such behaviors.
Since you are having difficulty finding her professional help, have you considered counseling services for yourself? I only suggest this b/c a professional may help you through your emotions and support you in setting boundaries. It's just a suggetion...I hope it's not too out of line. I do not think 'you' are the one in need of therapy, but I do think it would help your heart right now. : )