That sounds so frustrating I know when I have sessions where I can't get anything said it makes me want to give up too. It's like, what was that whole hour for?

But you know what, all of the (actually significant) progress I've made in therapy has come from the motivation that being frustrated has provided. When you can't do something you want to do... that is not YOU or your fault. That is your past interfering with you. You definitely can become more assertive and more able to focus on your own needs. It starts with this frustration. Bring that frustration to T, talk about that specific interaction in that specific session, since she has seen the problem in action. If she knows how you felt, she'll be able to help you better. Frustration is good. It is pointing the way to healing, but it's telling you that you need to hear yourself and be heard more than anything on this issue. Don't give up!