Her comments seem quite invalidating. But yet you stay, so you must be getting something? Or is it just too hard to move on, so you stay?

This may seem like an odd comparison, but at some point in my therapy, my T asked me why I was staying in the marriage. It seemed from what I was telling him that it wasn't filling my needs in any way. So he was just openly curious. In response, that week I made up a list of why I wanted to stay in the marriage and why I wanted to leave. I quickly wrote up 26 reasons why I wanted to end the relationship. They just flowed off my pen. Then I struggled quite a bit to compose my list of 6 reasons to stay. That's all I could think of. Seeing the lists side by side was really a revelation to me. I think this exercise helped convince me I really didn't want to stay.

Maybe you could do the same for your T. Write down the reasons to leave and the reason to stay. Then compare. Maybe this will make the decision clearer.