Wow, I guess this is one of the tangled webbs that can develop when the T-friend barrier gets crossed.

Let's assume that your T really didn't intend to get so involved in a personal friendship with you and truly cares about your well being. I kind of agree with Sunrise, as uncomfortable as it would be to do it seems like the best option is to be direct and tell her why her being your T is no longer possible for you.
It may help you fully end this relationship and possible help others who may end up seeing her in the future. I am NOT at all suggesting that it is your duty to protect others. I just think telling her how her actions have affected you might be one of those things that has a positive ripple effect in the long run.

Personally, I would not want to work my way through this VERY challenging situation alone...having another T to help you work through it might be helpful.