how the hell did the prince expect him to tell him about his problems when he knew that he...

he’s mad bc chen yu didn’t realize or want to believe how crazy the he is for him lmao.. i wouldn’t have told the prince either, even if i could

yeah but like when he was poisoned and thought that he wasn’t talking to him but it was because he couldn’t tell him that time because he was weak from the poison and didn’t know how to write

I think he assumed that Cheng Yu would know what he was doing when he raised him up to be his official concubine. That that would protect him and also showed quite definitely that the prince cared for him deeply.

Cheng Yu has been trained to appear to be a noble lady and he has been performing that role very well so far. If that moron doctor had not been so indiscreet, the princess could only hold on to her jealousy and still lash out because she is violent and impulsive, but she saw no flaws in Cheng Yu's facade to suspect that he was a man, let alone a man of low birth. So I think the prince himself thought Cheng Yu would have been trained well enough to understand what he was actually doing for him

He has accepted Cheng Yu, knows he is a man but Cheng Yu thinks this is some well kept secret and that the prince is unaware of his sex. So they are in two different wavelengths. He expects Cheng Yu to see his acceptance and Cheng Yu lives in fear that the prince will reject and kill him when he finds out he is a man.

Cheng Yu, now, also has the means to communicate with the prince (thanks to learning how to read and write) but his insecurities at being of lowly birth also play into his self sabotage and he starts thinking that he is "undeserving" or "unworthy." The prince may expect Cheng Yu to trust him but it is more likely that expects him to use his new position and the prince's affections to help himself to the prince's protection. He has hinted over and over that Cheng Yu can get anything from him, that he is willing to be used for Cheng Yu's benefit as long as the prince gets Cheng Yu's affections and fidelity but Cheng Yu feels "unworthy." He sabotages himself.