Hon, that's awful. (Hugs)
Sadly it seems you've found out now that she is an alpha female - queen bee if you like. She, until your reveal, had little to no competition in your area. And now she has, and she's in a really bad place. Talk to HR, but focus on the bullying/harassment angles, as you gain most traction that way.
We are all here for you, as always - you've been able to achieve so much already, you can do this too, in a heartbeat.
Rowan