A whiff of cologne. A snippet of a song. A news report on TV when you can’t change the channel fast enough. If you’ve experienced a shocking, terrifying, or dangerous event, the simplest thing can take you right back to the moment it happened. And you suddenly find yourself re-living the terror. That is post-traumatic stress disorder (PTSD).

Is today’s weather the same as it was *that* day? Are you wearing the same jacket, the same shoes? Maybe you just ordered the same meal, and now your heart starts to pound and your palms sweat and you’re shaking just a little bit. The nightmares have been robbing you of comforting, healing sleep, and you feel exposed and vulnerable. That is PTSD.

So now you’re always on guard, always ready to react. Now you’re easily startled, and irritated, and maybe feeling guilty. It’s not easy to maintain that level of hypervigilance. You’re starting to do things you wouldn’t have done “before,” like driving too fast, or experimenting with other self-destructive behaviors. The intensity is exhausting. That is PTSD.