I'm going to tell my best friend everything he touches is worse as a result.
Why would you say something like that to your best friend?
Because he is a junkie who ruins everything.
Having a friend with addictions would be hard. It's still rude to say something so hurtful to a good friend. I hope you have tried to get him to seek some help.
Fuck off, he's not a junkie.
You're not being very consistent here. If your friend really has a drug problem, I hope you'll help him find treatment, instead of just insulting him.