My separation agreement specifies that I provide health insurance for both my children (17 and 21). The 17 year old lives with me full time and my ex provides no child support. She, my ex, is no longer on the insurance policy. She continues to make appointments for the 17 year and taking her without consulting me. Some of the visits clearly fall under medical and some cosmetic such as braces and dermatology. As my child’s mother does she have the right to make appointments for procedures without my consent and at places I don’t agree with and have things filed on my insurance?

It depends on what your custody agreement says with respect to decision making. If you are required to make joint decisions regarding health care she should be consulting you.