Lost You Forever: Tushan Jing's story is about a superpower that is also a fatal flaw
I see so many people call Tushan Jing "weak" or say he's leading Xiao Yao on when that is not what is happening at all in his story or Lost You Forever. Tushan Jing is kind despite his trauma and this is both what Xiao Yao loves about him, but also the reason he just cannot free himself from his engagement.
All four main characters, Xiao Yao, Cang Xuan, Tushan Jing, and Xiang Liu, go through some sort of massive trauma, it turns three of them into fairly ruthless people, especially Cang Xuan. Tushan Jing is the only one who retains kindness and he even decides to forgive (but not forget) what his own brother did to him. Xiao Yao loves him specifically because he is kind, she doesn't want the typical male lead who is only nice to one person (both CX and XL) because as she so very correctly points out, if he falls out of love with her, he'd be cruel to her too. She wants her fox boy who is nice to everyone:
The problem though is she abandons Tushan Jing to a problem he cannot fix, and she knows this! I don't blame Xiao Yao, because she's got her own issues, but she fully admits she knew Tushan Jing would lose and didn't help him. She also never even told TSJ that his fiance was a murderer. He only saw Fangfeng Yiying's nice perfect daughter-in-law side, XY knew that FFYY tried to assassinate CX:
There are a bunch of reasons, all clear in the story, why Tushan Jing can't get out of his engagement and why his family won't let him:
He agreed to the marriage originally, to the point that he was kidnapped on his wedding day, so he can't even deny wanting it in the first place
The marriage was a deathbed arrangement by his mother
Fangfeng Yiying spent 10 years being the perfect daughter-in-law (and then an extra 37 coma years). Importantly, public perception sees this as love and the Tushan family really cares about their reputation (they are merchants, this makes sense). If the Tushan family suddenly threw her back, they would look like MASSIVE jerks. Even worse, FFYY comes from a lower status family, so if they suddenly threw her back and then TSJ married a princess, the Tushan family would look like even bigger, social-ladder-climbing, greedy jerks
If TSJ had come home and immediately exposed his brother, it wouldn't help break the engagement because FFYY had nothing to do with that and no one knows about the affair.
Grandma said no. Extra context: I know Cdrama grandmas love to say that they are dying if their grandchildren won't obey, but Grandma Tushan is certifiably dying. In the novel, she artificially extends her life until TSJ wakes up from the coma and has very little time left.
So what can he do? He tries to pay FFYY off (which she rejects) and he tries to convince his family. Unfortunately Grandma loves FFYY because she's been playing perfect daughter for decades and won't agree. The only other options are:
Kill FFYY. This is the easiest and TSJ could do it, I think two people also offer to do it for him, but here we have his perspective in the way. He doesn't know FFYY is an assassin or that she's sleeping with his brother. She plays a part in front of him of perfect fiance/daughter-in-law. He has zero justification to kill her except wanting to marry Xiao Yao. However, if he did, he'd be as ruthless as Cang Xuan and then Xiao Yao wouldn't like him anymore so this gets him nowhere. It is the ultimate Catch 22.
Give up all ties to the Tushan family. This would work, but there is a secondary problem which is that Xiao Yao is a princess. (She only reclaimed her identity as a princess to help her cousin CX and TSJ also helps CX for that reason) Tushan Jing qualifies (barely) to marry a princess, but without being the heir to a powerful and rich family, it's not really socially sensible (though we know the King of Haoling would allow it, Grandpa King would probably allow it but Cang Xuan might prevent it.) Anyway, TSJ does offer to do this at least twice, but XY herself tells him not to. It's not an option until the very end when his nephew takes over the family because they refuse to make his brother heir.
So to sum up, Tushan Jing can't break the engagement for many reasons, but mostly because if he something did dishonourable, he would become someone that Xiao Yao hates. The thing she loves about him, his kindness, is what makes it impossible for him to be with her.
Anyway, you don't have to like Tushan Jing, I think the drama did a disservice to his character by not showing him as witty and fun once he wasn't severely depressed. And I think structurally, the story front-loads a lot of his really good scenes and then at the end of the story we see more cool stuff from XL. But he's not weak! If choosing kindness was easy, he wouldn't be the only one who did it.
