Stepdaughter Needs Prozac...to deal with her mother?

I was texting with my 17-year-old stepdaughter today to find out how she's doing (panic attacks, anxiety, losing weight...she was just put on prozac which I don't think is the fix for her but what do I know).  She's away at band camp right now and she is fine.  She says she feels fine when she isn't at home (at her mom's).  It's when she is at home (with her mother) that she has the problems and needs the prozac to fix that.  That's what she told me. 

Um...what does that tell ya?

When she was here in April - not one panic attack, not one anxiety upset, she ate regular meals, etc.  She goes home to her mother's and within hours, she's flipping out with emotional meltdowns again.

The one place she should feel secure and safe, at her mother's where she spends most of her time, is where she loses it.  Why don't the therapists she has right now see this?  All the other therapists my stepkids have seen for the last decade all came to the same conclusion - their mother was their problem.  Why isn't her current therapist and psychiatrist seeing this?  I'll bet you that the ex didn't let them know she was fine when she was HERE and that it only happens when she is with her mother. 

I think hubby needs to send a letter to the therapist for his experience with his daughter when she's with us.

One more year, one more year.  I think I can, I think I can, I think I can...I'll be the little engine that could to get through this next year for my stepdaughter (though still have a few years left with my stepson).  I can't wait until she graduates high school and starts college so we no longer have the ex between her and us.  Which reminds me, I need to tell her about this place to sell textbooks after she's done with them in college for a little financial help.  I still can't believe she turned down two FREE years of college near us (special program through our high school) so she could stay for band her senior year at her current school (she wouldn't have needed the prozac either like she does while living with her mom).