Your phrasing is very apropos, since if the law is applied to her (which I believe is the question you are asking), it will almost certainly be applied to her "the way it has been applied to Petraeus", as opposed to the way it's applied to someone lower down the totem pole:
"[Former State Dept. official Stephen] Kim did not hand over a copy of the [classified North Korea] report — he just discussed it, and nothing else — and the report was subsequently described in court documents as a “nothing burger” in terms of its sensitivity. Kim is currently in prison on a 13-month sentence."[0]
For context, Petraeus "gave highly-classified journals to his onetime lover and that he lied to the FBI about it."[0]
[0]https://firstlook.org/theintercept/2015/03/03/petraeus-plea-...
2. I don't know, do you? My guess is that, yes, she did.
3. It depends on whether shared classified information with anybody who did not have clearance. My guess is that, no, she didn't, or this would already be a much bigger story.
Using a personal email address is not the same as sharing classified information.
But this issue isn't (yet) about handling of classified material; it's about government oversight.