So, I think a lot of people are upset because they don't understand. I had to reread this twice before everything fell into place. Lemme explain what I'm thinking has been happening.
From the start of chapter 1, we learn about a "Dragon who loved a girl", then it immediately starts talking about Aquila's birth. This is alluding to the fact that some way, Aquila must have been the dragon. This gives him supernatural human abilities, and strong magic. So, running over everything that has happened, basically in order. Lamia and her family were living happily, until Aquila stepped in and ruined everything. Lamia was destined to become the duke's heir, and Uriel, a knight. However, after Uriel's hand was destroyed by Aquila, Lamia and Uriel are forced to swap roles. Lamia cares very deeply about her brother. So, naturally, this would cause pure hatred against Aquila- let's keep in mind that Lamia has no idea who Aquila is, that much. In her eyes, he is a royal stranger who caused her father to disappear, who traumatized her brother, and then showed up later and declared his love for her. Yeah, of course that wouldn't spark a soft reaction from Lamia. So, this brings the question of, WHY did Aquila do everything he did?
Basically, this brings us back to the whole dragon concept. We know Aquila is a strong mage. Most likely, he has the ability to reverse time as well. Let's recall Chapter 3. Here, we see Lamia and Aquila planting a tree. Lamia says something along the lines of, "Spring will come". Then, winter rolls around. It's clear that Lamia dies during winter, and "Spring never comes to her". But that's still a little confusing, so I'll add some details I've picked up along the story.
Lamia is fated to become a duchess, and suddenly Aquila wants to change that. This leads me to believe that here's how their story goes: Lamia is the heir of the duke, and becomes the duchess. She falls in love with Aquila, and the two get married (We see them wearing wedding rings in chapter 3). All is well, until eventually, we are led to the gardening scene. Lamia and Aquila plant the tree, and she says that "Spring will come soon". Winter comes, and like I said, Lamia dies. Spring never comes to her. Devastated, Aquila reverses time. He meets Lamia again, the two get married again, Lamia still dies in winter. Aquila keeps reversing time, trying to find a way to stop Lamia's death so that he can have a happy ending with her. Each time she dies, Aquila reverses the time. [While I'm not sure how long this cycle has been going on, it must have been happening for a while, judging by the amount of times "Lamia" and "Orphe" were inscribed on Aquila's back in chapter 38.]
So, Lamia dies again, and Aquila reverses time. However, he decides to try something different. His thought process was probably, "Can I change Lamia's fate by making her a knight instead? Can we finally be happy together?" So, he was probably thinking, if he harmed Uriel in some way that made him incapable of becoming a knight, he could change everything. And that's just what he did. He destroyed Uriel's hand, causing Lamia to become a knight, and changing everyone's fate. HOWEVER, what he didn't see coming was Lamia's hatred of him to follow. Lamia cares about her family, Lamia doesn't know who Aquila is, as I said before. So for her, she hates Aquila. She never wants to see him again. While she hasn't died in this timeline, Aquila did screw it up. They didn't get their happy ending, because Lamia hates Aquila. And when she told him, "I hope spring never comes for you" without understanding the full meaning of it, Aquila did. And to Aquila, Lamia just told him, "I hope you die".
Anyways, I hope this helps clear things up regarding Lamia and Aquila's history. If you have a question, please ask, maybe I'll be able to answer it!
