Abby didn't hate Ziva because she was jealous of her- how everyone liked her, how much she was respected, how easily she replaced Kate.
No, Abby wasn't jealous.
Abby was angry.
Kate had been handled and kidnapped. She risked her life to stay with a Plagued Tony and took two bullets for her boss.
Now she was lying in a box six feet below ground with a hole in her head and Tony was lusting after the woman who replaced her; the same woman, coincidentally, who was supposedly looking out for Ari when he murdered Kate.
No, Abby wasn't jealous.