Spoiler...
She will eventually find out because at some point, she put a tracker on him. And in one chapter, she saw him removing his "mask". I left a lot of details so you can look forward to it.
As for if she'll fall in love before she discovers who he is, NO. She was really in love with her "husband". And expect her revenge arc. It's very satisfying. The ML will only know the she already knows once she executes her revenge. Do you wanna know about her revenge?

Not really soon tho. But I just finished reading what's going to come after this and oh boy, it's going to be amazing. The tables will turn!!!!