From Season 7 Episode 2 - Reunion.

Ziva: Hello Abby.
Abby: (turns music off and glares at Ziva) What the hell is wrong with you? How could you have doubted Tony, after everything you guys have been through together? You really think Tony killed Rivkin because he was ‘jealous’?!
Ziva: Abby, please calm do-
Abby: You weren’t thinking! That’s right, you weren’t thinking! Although… I suppose I could understand your initial reaction… you were in an emotional time for you and people act rashly - but to tell Gibbs you didn’t trust Tony?! Which… I guess I could also understand, considering. I mean, he did just shoot your boyfriend. In your living room. To death. Alright, I’ll give you that. But this is Tony we’re talking about here; soft and goofy on the outside, and 100% rock on the inside! And after everything you accused him of, he risked his life to go save you! You should be ashamed of yourself! Even though in hindsight, it’s starting to make a little bit more sense now. But either way - the ball is in your court now! It’s Tony one, Ziva zilch! It’s your move, and it better be a good one! (pauses) God, I was so worried about you. (gives Ziva a hug)
Ziva: I know.