92 year old mom has always had issue with anxiety, but now she is completely out of control, no one can live their lives,needs constant attention,will not see doc,just walks around moaning of stomach ache.. its impossible, is there anything i can do?

This is very difficult. An elderly person with anxiety can cause stresses in the entire household. Since you cannot control her behavior, you will want to arrange for some respite time - an adult day care setting or even temporary (even a weekend) respite through a nursing home. The respite is for the family. Having a doctor or visiting nurse or chaplain come to the house may be helpful.

Dr Horn's management advice is indeed helpful, and likely will ease burdens. BUT, suspect her symptoms represent changes in underlying brain function such as vascular or Alzheimer's causes, and this needs to be assessed as symptomatic treatments are available.