I get angry at my T on a regular basis. There's lots of reasons, but most of it is not T personally - he's just the one I'm interacting with at the moment, and I'd probably feel the same way toward someone else in the same circumstances. Talking about it helps me to understand myself better and r/s stuff.

Like you, sometimes I just get furious because his life seems so perfect and mine is......well...... not.

Talk to her, and tell her about what you're feeling. You can even say something, "This probably isn't really about you, but I'm just feeling really angry at you and it's confusing me" or something. Like others have said, she'll know it's not about her. I think it's all just how therapy works, the conversation and dynamics between 2 people.