I can relate to a lot of what you said. I'm guessing from the syntax that you're a Brit/Oz/Kiwi and therefore a citizen of one of those places. There's no reason to be terrified of the future. Luckily, our countries have welfare systems. Get on to your embassy, explain the predicament and ask what help might be available once you disboard the plane in London/Sydney/Auckland. Lots, probably.

Though it seems like a &%^*&*% mountain to climb (I know - I've stood at the bottom of it myself), try to re-establish contact with family. You probably haven't done quite as much damage as you think you have, and you might find them very willing to meet you halfway.

Get rid of the gun. The worst day in China is better that having your brains all over the kitchen floor - much better.

Nearly finally, there are plenty of nice women in China who'd like to meet (and live with, and take care of) a foreign gentleman. If you opt to stay, that can make a huge difference. I know it did for me.

Not quite finally, WHERE you live in China is crucial. Somewhere like Beijing/Shanghai/Guangzhou is far better than the sticks of Jiangxi, Hubei, Hunan or Henan. Consider a move. It's not like there's a shortage of jobs.

And really finally............GET OUT OF THERE AS SOON AS YOU CAN. It sounds like you're depressed and in sore need of a change.

Life is good and you are not alone in this. Your situation in China is a very familiar one. There are thousands of us.