I saw a therapist for a year twice weekly and we terminated last June (due to my relocation). I also grew very attached to him and I knew that termination would be painful. As we both knew about the termination in advance then we were able to talk about it quite a lot.

He told me that he wants me to be able to talk about our relationship to the other T I would be seeing after that. At first I couldn't talk about it a lot and I didn't even feel sad, but after few months the sadness really kicked in. I think I grieved heavily for about three months. After that I had established good enough connection with the new T (who was actually my old, but never mind the details) and I was able to talk to him about the ext-T. Now, more than half a year later I still remember my ex-T very well and I still think very fondly of him. But I'm not sad and it doesn't hurt me. I know that he remembers me and probably thinks about me occasionally. I also know that our relationship was meaningful for him too.

So, yeah, time will do its work but I think it would be also very good if you could talk about it to someone. Someone who would understand how important a therapist can become to a person. It could be a friend, it could be a family member, it could be a new T.