
I’m pretty sure the chouxi’s dad has something to do with the way yeyu acts. In one of the chapters, yeyu goes to reach out for chouxi then flinches away, remembering someone (the dad??) slapping him and calling him disgusting. So, rather than being a coward, I’m pretty sure yeyu just has a lot of unresolved trauma that’s clouding him from seeing chouxi’s true feelings- he probably thinks that chouxi will react like the dad did if he finds out that yeyu likes him.

Jiang's probably still traumatized from Chouxi's father. The reason why he is scared to express his feelings is because of the dad probably telling him hurtful things like he is disgusting and such and eventually pushed him to move out. It broke his self-worth. Imagine being treated like that by a parent (even if he's just a stepfather).
Chouxi, on the other hand, didn't experience that kind of ostracization so he's courageous about expressing his feelings. He doesn't hide it because he doesn't feel the need to.
Sure. They both have feelings for each other but their experiences are different.
So let's blame the dad
Why does the uke keep running away? Is he going to live in denial for the rest of his life? In the raws, even when the seme kiss him and tells him he likes him, the uke still runs away. What the fuck is going on? If the seme is straight, it’s one thing to refuse. But your crush is gay and he likes you back, why the fuck do you continue to be a coward? Falling in love with a coward’s the worst thing you can ever do. The seme tries to understand the uke and when seme found out that he’s also gay and like the uke, he didn’t shy away. He try to make it work. The uke never tries. Even when the seme comes to him, he didn’t try to work out his feelings in a healthy way. He push those feelings down and push the seme away. No wonder the seme was angry when the uke left a few years ago. Leaving without a word, it made the seme wonder what he did wrong. Sorry but I really can’t sympathize with this kind of person who’s always passive, lacks courage, and full of self-pity.