
SPOILER
He is a massive coward. His mum didn't want him to marry with Leila so she did something then she got exposed and embarrassed etc etc and Leila didn't wanna get between son and mother so she called it off or something like that. also Kyle was very indecisive so they marriage never happened. Then after some other stuff happens Kyle wants her back but it's too late bc of Matthias. I don't remember well, so anyone can correct me.

Spoils
Unfortunately, Kyle's mum sabotages Layla's entry to university by stealing the tuition money. The shameless lady even confesses her crime to Layla, plays psychological games with her and humiliates her, saying that Bill made a mistake when he decided to raise her, making it very clear how much she hates her, all because she thought her son deserved to marry a girl of noble blood.
This came as a huge shock to Layla, because the lady had done this a few days after inviting them to her house for dinner, showing her acceptance of their marriage. Layla's intention was not to tell anyone, swallow her tears, cancel the engagement and just take Uncle Bill's money back. But as Mathias has learnt everything (via espionage), he decides to take revenge for Layla by exposing Mrs Ettman to the police via third party.
Kyle were totally shocked and unresponsive when he abruptly learns the truth and sees his mum going to jail. He takes a few days to process what has happened and then makes the decision to suggest to Layla that they run away together. But as he was still a bit dazed by everything that was happening, he takes a rather brusque approach to Layla, who clearly refuses to go with him, and is then caught and thrown out by Uncle Bill.

However, in all this confusion, it's Mathias who comes out on top, taking advantage of Kyle's estrangement to gain a foothold in Layla's life. And she, weakened by everything that has happened, ends up losing her resolve to leave Arvis.
My opinion
Despite all the damage done by Mrs. Ettman, Kyle and Layla's marriage was doomed to fail from the start. Any incident, no matter how minor, would have shaken their relationship, due to the fact that Layla wasn't in love with Kyle and had no real conviction to fight for their relationship. It was fine not to get married, but at least to go to college and be as far away as possible from Mathias' harassment, which clearly showed what he wanted from her. But she wasn't able to do that because she felt somewhat attracted to him. It was only a matter of time before the two of them consummated the act after so many stolen kisses.
Please author. I'll cry and i'll beg, please, make kyle and leila endgame. I want the duke to suffer with Claudine please