Spoiler
I don’t think he’s in love with the doctor because when zishu dies, he tells the doctor that the doctor reminds him of the younger jiang. Ig zishu liked him but more so because of how he was extremely kind, like the younger jiang
....... my depression is suicidal
technically they weren't together, it was mostly out of obligation but also because Ziyu reminded him of young Jiang.
Because Zhishu knew he was going to die, and there was someone he loved he wanted someone to be happy because of something he had done, and Ziyu knows that, that's why he cries before doing the "deed" (I'm pretty sure they didn't do the stuff that needs to be censored, because then Zhishu wouldn't be able to walk)
I kind of don’t understand is Zishu really in love with the doctor? Or is he with him as a sense of obligation since the doctor treats him so well?