She really won't be surprised. It possibly isn't even transference at all, although, arguably, all relationships have transference. Its perfectly normal to go through a clingy, obsessed, idolising stage in therapy, especially attachment based therapy.
It's just a phase and most of us experience it. Sometimes it manifests as you are experiencing it and sometimes it takes the form of a crush or even feeling like falling in love with them. Regardless of what sex or sexuality you are.
It passes. I'm mostly coming out of that phase now and settling into secure and comfortable stage. My therapist was neither shocked nor particularly bothered by it and said it was normal and just part of forming a secure attachment. .
That it wouldn't last much longer than my insecurity in the relationship and that once I was able to relax and trust in it, the crush would just fade away. He was right, it has.
I mean, I still absolutely would... and I'm pretty sure he knows that! 😂 But I don't really think about it much outside sessions anymore.