The dude was speedballing, so yes you have a death wish if you partake in speedballing. Even if you don't have a death wish using hard drugs means that you are slowly killing yourself.
As for your analogy- speeding or not you can be killed driving a car. 100% of those that drive could possibly be killed in a vehicle, 0% of those that do not take drugs will die from a drug overdose- so in my mind you are harming yourself on purpose if using drugs which in a way is committing suicide.
Slowly killing yourself with drugs or any other unhealthy life choices and deciding to commit suicide are clearly different things. My speeding analogy wasn't even so much about speeding as it was the fact that tons of people die in car accidents every day. People take all kinds of risks with their lives on a daily basis but for some reason drug addicts get no sympathy and are accused of taking their own lives.