In the past we used stress well and needed it to survive. It worked perfectly when we were back in the primordial swamps, when we were all gatherers and hunters and - in my case, my ancestors were known as pointers: the Jews. We just pointed at things saying "I want that." Then when something with large teeth came along our fight or flight response would kick in and, if we survived, we'd all go back to our normal lives; hunting, gathering or in my people's case, pointing.
These days we're always in fight or flight mode. It never shuts down because the threat is invisible things; we can't fight mortgages, losing our jobs, paying rent. You can't run away from the national deficit. The brain still thinks it's in the Stone Age, it doesn't realise it's in the 21st Century. It still just knows to scan the surroundings for what's dangerous (is it a snake?) and what's safe (is it a stick?).
Here's the biggest worry of all as far as our survival and it's not invisible - Donald Trump winning, be scared be very scared.
I'm not saying we have more stress than the third world. Stress is different, they're living in terror and terror is not because of something going on in your imagination, it's a real emergency. They have to be in fight or flight or they don't make it past the next hour. If the terror becomes unbearable they become traumatised, which means they freeze.
As I said, in this culture the enemy isn't tangible and so our minds try to figure it out. Our brains go into endless loops, never coming to any conclusions. Each thought daisy chains onto the next keeping us up at night and sometimes it's about something mundane like "Why did Bob not call me back? It's because he hates me. Why does he hate me? Because everyone hates me, I even hate me because I'm such a wanker for thinking about why he didn't call me back? When did I become such a wanker? You've always been a wanker."
This kind of thinking is called rumination. The word is based on a cow chewing its cud. It chews some grass, then swallows, then it vomits it up, then chews it again then vomits, it never ends. That's what we do but we're not cows.
There will always be stress to keep us on our toes, keep us advancing but if we want to survive we've got to learn to recognise when we tip into rumination, getting stressed about stress. To understand that the crisis isn't because of something outside of us that's burning us out but that the crisis is inside. We are the problem.
Ruby's new book - A Mindfulness Guide For The Frazzled - is out now and available in all good bookshops, as well as online.