How long has she been taking these meds? Is it possible that she does not feel like herself when she takes the meds? I remember when I was taking Adderall for ADHD the symptoms improved, but I didn't feel like the same person anymore. I wasn't me. I eventually stopped taking it for other health reasons but when I did I felt like I was me again.
Perhaps that is what is going on for her? Maybe this medication works great for improving interactions with her but it alienates her from herself?