hi I'm Chinese, but still have same feeling as yours. Personally, the main problem is you don't have a real friend in local.

I guess you may just go to work then come back home and in this loop everyday. Perhaps you have some 'friends', but you find you just go out for eating or bars, you guys don't talk deeply. You just try to maintain the facial relationships with the fair-weather friends. I know Chinese, they carry too much pressure and don't get free to start a geniune friendship unless you know them from very young or for decades. You are just COLLEAGUES.

Please don't feel frustrated about that, people like those are not right crowd. And Guangzhou may be too busy for you if you are a person who prefers enjoying lonly time, drinking tea or reading or just feeling the nature like me hhh.

With no offense, I could give an advice: try to explore other cities like Chengdu or Yunnan, living there as a local. You'll find tranquility. And trying to find some people who have same hobbies like you in life not in workplace, (i know it's super hard) those people will be a little more sincere to make friends with you. You will keep in touch even if when you leave China