YEs I have felt this. I certainly was told frequently enough that I wasn't the same and didn't fit in. (I wasn't adopted)

I wonder if your therapist phrased it that way, perhaps, because she now thinks you are ready to hear it? How would you have responded if she had said it much earlier?

I always think if something sticks with me from a session, then it is something worth bringing up again. My therapist happens to agree with me! lol