Reading her public Facebook page (or even trying to read her protected "private" one) is not intruding into your therapist's life. Any feeling of intrusion is your imagination, she has no feeling of intrusion by you or she would raise that issue with you (that's a personal boundary thing). Telling her you go to her page often, is about you, not about her and it is just words on a page, not "her" or her actual life. That you feel you can imagine what it was "like" at her daughter's birthday party in the park in no way means you were a part (past tense, as well) of the party/her life and predicts nothing for the future. Knowing she has a daughter/child/husband/relationship with X, she posted what she posted on her page -- it is her responsibility. She does not discuss it in therapy because therapy is about you and your life, not her and her's.

I cannot see her being disappointed in you for being curious, interested in seeing how she lives, etc., humans are -- that's why Facebook is so popular in the first place. However, if you continue to dwell on her and become obsessed with her instead of working on your self in therapy, then she would have the problem of not being of any use to you so not wanting to take your money.