It's not fair...

I hear that, but I don’t think it was your responsibility to know what your copays are. When therapists decide to take insurance, they are responsible for verifying that information (that’s one of the reasons many therapists don’t want to take insurance in the first place - along with having to wait for insurances to reimburse them). It sounds like the financial aspect of her business has become a bit disorganized IMO, but that’s not on you. Also, I mean no offense to your T - I know the relationship means a lot to you.