I think first I just told my T that 'I really like' him. Then a bit after that I started talking about how scared I am that he will abandon me, hurt me, and so on. I never explicitly stated that I am attached, but he still seems to get it, since he asks things like whether my mood swings are connected to his vacation or since he will offer to see me on another day if my usual session day falls on a holiday (things which he did not do before we started talking about these things).

Overall, he seems very comfortable with the idea that clients get attached to him. As others have said, it's pretty common. He didn't really comment on it too much. We can always talk about it. Sometimes if I talk about something different, he will also ask whether it might be connected to being attached to him.