OP,
I've only just started this (thru ep 5) , but have skipped ahead enough to know where it's going. I don't see where she deliberately decided to use him to take revenge on her ex & his GF? To me, it seems that she was ambushed by her feelings that she's been in denial of because she cares more about her pet project and she's hurting by the betrayal she's suffered.
Let's face it: She's a career-person. She uses him to further her career and as the cornerstone of her proposal to get the e-magazine off the ground. I won't comment on the reality of this actually happening as I don't know the Chinese domestic market, but let's assume that it's possible. And her boss uses her connection to him (although unaware of how deep the relationship is) as well to push things along. So she's being pushed along this path towards him, while being completely unaware/uncaring of his feelings.
We know that he's been smitten with her since the beginning and finds her fascinating. (Dylan does a fantastic job in recreating the character in the novel: the way he looks at her, with that curious, disbelieving stare, is almost like an entomologist studying a new species of butterfly, and is both funny and sad. He's so awkward when he smiles, I almost LOL).
So, she uses him throughout the series to achieve her professional goals, while trying to ignore the fact that their 'relationship' is plagued by misunderstandings and lies she's told him. Is her inability to be completely honest with him a sign she really doesn't care about him? Or is she so used to saying anything to get whatever she wants, that it makes her lying simply part of who she is?
I think I would have slightly tweaked the series/novel to make him use her industry contacts for intelligence purposes - so we'd have 2 people using each other for their professional gains, while unexpectedly falling in love.
But, she's cute, and ruthless, while he's smart and clueless. He'll get blindsided eventually and it's going to get ugly because he won't know how to handle it, except maybe to run, which he can't because of his job. In the end, it's a story, and there for us to enjoy or complain about. So far, I'm in (but I like slow-burn stuff).