Possibly he is drawing the line in the sand for you both? As you've said, he is quick to turn when you venture near his family. You've also said he may be overcompensating, and maybe you're onto something there. Maybe he is self-correcting, to remind himself that he is the therapist and not the parent, even though he seems to have strong paternal feelings towards you. Vice versa.

If your litmus test is "is this therapeutic", I think it's helpful to realize that this (what you are experiencing with T) is the real meat of some of our therapy. To explore the neediness, the emptiness, the loss, the abandonment, the unmet needs. It sure as hell doesn't feel therapeutic. It hurts like hell. But I think this is therapy. To me it sounds like you've hit up against a wall, where he is unwilling to be flexible. I would feel the same way, Echos. I'm not sure what I would do in your situation either, but I do know that if I've invested as much as you have, I'm sticking with it to see if it can be worked through.