No one likes insurance companies. I promise you they are as much a headache for the provider as for the patient (I am both, obviously, and I know this is true)! However, when a provider decides to work with an insurance company they agree to abide by the rules. No one forces me (or your t) to take insurance. If she hates insurance companies then she would work in cash and just waive your fee. Plenty of t's do that.
I agree with the above- insurance companies are slimy and gross, but a provider with personal integrity stands by what they agreed to do.
Again, so sorry you are caught up in this.