
To be fair, they're both afraid. They both only experienced being loved sincerely briefly in their childhood (Lucia by her mother and Hue by his brother). So they don't want to risk being distant by confessing.
Lucia cannot confess because obviously if she did, and Hue didn't like her, their contract marriage would have been over.
Hue has low self confidence due to Lucia's "indifference" to his past love life as well due to her words that she will never like him. The fact that Lucia didn't tell Hue that her nickname was Lucia, but told Damian and her friend, probably also makes him feel she doesn't care that much for him.
Can they just converse? Half of the misunderstandings in this book won't be there if both of them just open up and converse. Especially Lucia, she's keeping so much to herself