How can one diminish a 'high stakes' type mindset in life?

Was reading an article on PTSD and the triggers. It said many experience*high stakes* type living with the disorder. That hit me like a ton of bricks. THAT is how my entire life has been and why it's been crippling the last several years. I'm a people pleaser and so avoid conflict.

Because I was bullied, screamed at or attacked if things were not perfect growing up, I developed a fear of needing to do everything right. It was exhausting which led to everything in my life being high stakes. It's why I don't date too and am petrified. If I don't offer a full package, and I don't, then I feel I won't have worth to a guy. How can one start to live WITHOUT a high stakes mindset?