Just as she was about to rip her descendant's heart out of her chest, Elena forced the cure down Katherine's throat, which resulted in Katherine returning to a human/Traveler for the first time in over 500 years.

Who did Katherine Pierce really love?

The complicated, romantic relationship between the cured vampire/human doppelgänger, Stefan Salvatore and his former sire, the cured vampire/witch doppelgänger, Katherine Pierce. Katherine fell in love with Stefan when she met him in Mystic Falls in 1864.

How Does Katherine come back from the dead?

She was sucked into Hell after not being allowed to go to the Other Side. After Katherine was sent to Hell, she manipulated Arcadius since the minute she was there. She eventually returned became an ally of Kai Parker and after Cade's death and became the queen of Hell.