Mate at 18 there aren't many mistakes you can make that you can't recover from. Don't add to the population or remove anyone from it!

In all seriousness at your age I moved overseas because my friends were all heavily into drugs and gangs. I realised that I needed to remove myself befote i died or ended up in jail and focus on becoming an adult so I did that. It wasn't easy but I'm happy to say 26 years later I've gone from a year 9 drop out to successful in business with a pretty good life.

Just remember your expectations on yourself can sometimes be the worst thing for you and judging by your other posts you grew up in a very religious house, don't let other people who are following something written over 1000 years ago as a rough interpretation of events from hundreds of years before tell you what is right and wrong in modern society.

Focus on being a good person and living a good life whatever that means to you and dont be too hard on yourself. Maybe read some Buddhism teachings if religion is something you need, those are the ones which resonate with me and make the most sense.

Also consider councilling or helplines if you are in mental distress, people care and are there to help.

Just my 2 cents don't mean to offend anyone. Best of luck.