It sounds like you have very clear thinking and you know yourself better than others know you. You know you haven't been depressed the whole time. It was hard to react in session, and easier to think when you're home and have time to think of how to respond to T's assumptions and judgement. Just becasue T says something doesn't make it true. There is no benefit in believing that you have treatment resistant depression. Instead it may probably best to focus on what you can do to make yourself feel better. If I were you I would also feel a bit weird to have T make assumptions about me. Hope you're able to talk to her about this!