This is a subject vs. object test. It must be "she" because the subject must be compared with another noun in the subject case. What's more, if you were to use "her" the sentence would be nonsensical, seeming funny, as if "her" were a modifier; you'd almost ask yourself "her what?" Comparisons in general are difficult because tr reader has to located what two things (or people) are being compared, and mostly anything is fair game in the comparison clause. I hope this helps.Posted from my mobile device
A few kudos won't hurt.