The fact that you become friends with your therapists actually says more about them than it does about you.

I think you need to decide what exactly it is that YOU get out of the continued contact with your ex T, aside from the attraction and obsession. If the attraction weren't there, would you still be in contact with her? My take would be to cut contact, but I know that is easier said than done. I'd be curious to see what your new T advises. Good luck!