
It’s complicated. Spoiler
According to what Carcel later believes, the crown prince trampled on Ines and treated her terribly and then after she killed herself before his eyes, he became obsessed with her and might have realized too late that he should’ve treated her better because he liked her on some level. The crown prince does have a reason why he trampled on Ines. It was partly for revenge.
Most readers like to think these characters are one-dimensional but they aren’t. They are fleshed out characters in the novel although the crown prince does have an air of mystery since the reader is hardly ever privy to his thoughts.

Spoiler
Since you ask, there is a timeline before the timeline Ines married the crown prince. In that earlier timeline, her brother and the citizenry rose up against him and he was arrested and executed. After he died, in the afterlife his wish was to retain his memories and the angel of resurrection granted his wish. (A person who died in a way he was not fated to die are granted wishes in the afterlife) Therefore, he lived again and used his memories to win Ines over to be his future wife. Instead of treating her well, he treated her terribly as revenge against the Valeztenas and particularly her brother. Little did he know that after Ines killed herself and he was deposed as crown prince again, her brother once again got his hands on him and tortured him every day by cutting off his limbs one by one. The deposed crown prince then killed himself and that’s how he retained his memories of timeline 1 and timeline 2.
See, when a person kills himself like Ines killed herself, they regress ten years with their memories of the previous life.

Oh wowwwww I did not expect these plot twists. So this is basically his 3rd timeline. It's a lot going on so now he just basically regrets or recognize that she was innocent bystander so he wants her back. So did Carcel kill himself too? For him to figure out why the crown Prince is obsessed with her. && The Emilio guy he must remember the past as well since he still got the gem? Cause I found that odd that he would still have it if time reversed.

Explanation
This current timeline is the fourth one.
1st timeline: Ines dies from terminal illness
2nd timeline: crown princess Ines commits suicide
3rd timeline: Runaway Ines commits suicide
4th timeline: current timeline
As to memories, there are two ways to get them:
1. Commit suicide
2. Die outside one’s fated death and the angel will grant the person wishes so that they can get an advantage when they begin their new life to correct their fate.
Oscar was able to make a wish after he died outside his fate in the first timeline. He used his wish and asked to retain his memories in the next life. He then committed suicide in the two subsequent timelines
Emiliano died an unfated death in the third timeline. He was granted a wish and his wish was to retain his memories so that he would stay away from Ines so he doesn’t hurt her. He didn’t stick to his wish so Angel intervened to stop him from trying to interfere with Ines’s fate.
So that’s how all of these characters have memories. Ines committed suicide twice but does not remember timeline 1.
Carcel died unfated deaths in all three previous timelines but his wishes in the afterlife were always about Ines and praying she lives a better life in the next timeline. A person only relives their life until they correct their fate. It’s not an infinite number of lives.
Carcel getting memories is a defiance to the established manner of gaining memories.
Hope this helps.
Can someone refresh my memory on why the Crown prince is so obsessed with her? Especially with the way he treated her. Is it just some power thing? I can't remember