"But attachment to T feels much more emotional than my RL relationships."

That's a good thing. If you have no feeling RL relationships, you are missing what is good and interesting about Life itself.

Your "T is not a friend" is avoiding the comparison :-) For me, friends are just "there" usually, don't make sense? We are attracted to them in some way.

Can you get your head to go the whole head way? T can be a bridge between your emotional brain and rational brain and teach you how to help the two work together. It "makes sense" to me that I would want that?