I know written is different than verbal, but from what I read it sounds like your T meant "But you would lie to me?" I don't necessarily think it's jealously. It might be him figuring out where he stands for you. I assume (so sorry if I'm wrong), that some of your therapy is around T1? So if he knows your thoughts and feelings are with him and T1, he can better gauge your progress. Maybe? Just trying to give you a different perspective.

Maybe what's important here is not how your T thinks or feels, but why it bothers you that he might be thinking/feelings a certain way. What does that mean to you? Would that affect your relationship with him? Could it be that you're comparing the two, not him? Again, just trying a different perspective.