You could look into studying? Education is pretty cheap over there, or even free if you can get a government scholarship. But yeah, otherwise working is the only real way to exist long-term in China.

Even then there's a language barrier to consider, and I heard it's difficult to learn them, Mandarin, Traditional Chinese, Simplified Chinese, etc.

Less of a problem than people think. Not endorsing the attitude but I knew foreigners who lived in China for years without knowing a word of Chinese. You can go with nothing and learn on the ground.

Plus, loneliness.

China's the same as anywhere, if you're relatively outgoing you'll make plenty of friends quick, and yeah foreigners do get a little bit of a boost just by standing out. Foreigners dating locals is very normal too, there's not really a stigma against it. Much more common for foreign men than women though.