No, you are to blame because if you are that freaking allergic to peanuts, you should not be stupid enough to be eating anything you didn't prepare from scratch yourself, or have verified beyond a shadow of a doubt is "peanut free". It is reckless for you to simply pick up a pack of cookies, and with a cursory glance at the label, eat them when you know that the difference between life and death, or walking around normal and a hospital stay, is trace amount of peanut oil.
My health should not depend on reading the fine print on a food package.
Of course it should. Manufacturers are responsible for making a good faith effort to inform you of the ingredients used in their manufacturing process. However, you are still ultimately responsible for ensuring that it is safe for you as an individual to eat because those same manufacturers cannot foresee every problem that might ensue from the use or misuse (which is what I would call you eating that cookie) of their product.
Col Sanders