It's possible that if you don't speak up and say what you are feeling is wrong in the therapeutic relationship that your T will believe that there is nothing wrong (and also not understanding that it is negative for you in some ways) and therefore you have made more progress than you really have. Sort of like when you go to the doctor and don't speak up about how you have this pain or that pain that he or she can't help you resolve it.

You could tell her that you are afraid to talk about the therapeutic relationship because of what happened with your previous T and start the conversation that way. You don't have to say that you're afraid to say something negative and you don't even have to say what's negative.

In the past it seems like you respond to any suggestion to speak up with one reason after another for why it's impossible for you to do so. This is something you can work on in therapy and I suspect it may help you with other relationships in your life (if you need help with them). Fear is a problem for almost everyone but you can take small steps towards moving forward even if you feel afraid. There is some famous buddhist phrase that goes, "feel the fear and do it anyway." I've not found much wrong with that approach.