I'm late but I'm adding my two cents.
The novel was so good. I think I'm a bit upset that in the show they portrayed him pretending he's her husband as this huge crime he committed. I mean, it is definitely a con and horrible of him to deceive her, but I'm upset that the show removed the reasons why he kept it up for so long beyond the fact that he was falling in love with her. As far as he knew, she was kidnapped and made a concubine to a bandit (does not know if it was willing), she stole from the bandit a significant amount of money that had people coming to kill her, she was chased off the mountain and lost use of her arms and legs, and was almost drowned.
There was a whole part in the novel where he was genuinely concerned about what would happen to her if he let her go, beyond the fact that she would be alone. He was worried for her life, she couldn't protect herself. It feels like that wasn't even addressed in the show. Instead, she was completely capable of protecting herself and even on nearly completing an assassination against those who wanted her dead.
So I'm kind of bummed that they made the whole dilemma between them the fact that he lied, instead of the fact that he slept with her while he lied (didn't happen in the show) and that he wanted to make her a concubine (was barely even considered in the show).