I totally agree with what you're saying and I think that's very reasonable for you to want her to give you reassurance that she will see you through this, that she won't abandon you when you are vulnerable. But do you mind explaining a little more what do you mean by trust going both ways?

Because it seems to me that the only issue you are talking about is trusting her (not the other way around); however you are suggesting she has to earn your trust. Obviously you are ware that you need to trust her, to have her guide you through difficult and dangerous train of this therapeutic journey, but you are suggesting that you will not follow if you can not be completely sure that you will not be abandoned half way there. Which, again, is totally reasonable.

On the chance that this is correct, then in my view you can consider two issues: One is why you don't trust her enough and two, what she needs to do to put your worries to rest. How can she earn your trust?

I think trust means allowing yourself to become vulnerable, to depend on someone. For a person who is depressed or anxious, this is especially difficult, because one is already feeling vulnerable enough as it is. So I think you might want to really talk about this with your T, about where you are at and what you need to be able to trust her.