This is really common. I felt the same with all my therapists and a couple of teachers and other people. It's a natural response to the therapy relationship and it is absolutely nothing to be embarrassed or ashamed about. A lot of therapists look for these kind of feelings because they link to childhood pain as you know. If you are able to talk about the feelings with your therapist and bring them into the room this can create space for healing to begin. It depends on the therapist and client of course and how well they work together and a lot of factors but in an ideal world this is the goal. So having a strong attachment to your therapist is not wrong, its natural and hopefully getting in touch with the longing will be helpful for you in being able to come to terms with the past.