I don't get it!
At the end did Zee sleep with Stella at the end in order to prevent her husband from leaving her, or was Zee an actual lesbian?
I took it as Zee did it to prevent Stella from further having anything to do with Robert because Stella would realize she's a lesbian and no relationship with a man would work, however Zee's plan didn't do any good because Robert was already thinking about leaving Stella for his secretary.