I usually ask them, "what exactly is that reason, please enlighten me"

Just remember, unlike religous nuts, an atheist has everything to live for and nothing to die for.

what do you want people to say to you if you are discussing your near demise?I would have a hard time not saying you are lucky

Things do happen for reason(s). It's just not the stupid reasons that they're thinking.

I guess that everything happens for a reason (all effects have causes), but I don't think that's any reason to be too teleological; that is, surviving a car crash doesn't mean that God has a plan. Rather, it means that because of whatever physical causes, the effect was that you wrecked the car, but you did not die. Even if the vast majority of people who are in car crashes die in those crashes, not everyone ever involved in a car wreck would be expected to die from the crash.

Tell those people that, indeed, you've found your purpose: to undermine people's infantile belief in God. That might shut them up.

My boss told me we are all born for a reason. I disagree. I hate that people think that karma is real and there is a higher power granting good people wishes and dealing out punishments to assholes. Nothing happens for a reason. It's just life and coincidences. There is no god giving out good luck and bad luck to humans.