A badass character from the CW's The Vampire Diaries played by incredibly beautiful and talented Nina Dobrev. We use it to describe someone who has been through a lot and still is awesome. "I'm Katherine Pierce, I'm a survivor." It's what she once said so phrase is from there.
"Megan's boyfriend cheated on her with her bestfriend and she hsd been into a terrible car accident. She's okay now, she's Katherine Pierce."