Thanks for this thread Asia and I will be very interested to read the replies.
I am in the same situation as you, I felt abandoned with t1 after our termination. I got too attached to her too quickly and she didn't like it. She had a whole different view on therapy and attachment was not part of the process.
I have never had a secure attachment so this is all new to me. I am trying to form a secure attachment to current t but I still worry that every session will be our last.
I always have this fear that everyone will leave and usually they do.
When I was a child my grandparents died when I was very young my brother and sister left and my parents left too(emotionally).
My friends all left when I started work much earlier than them, so yeah I have a deep routed fear. And then my partner left too for another woman so this is the main reason I am in therapy.