this was totally me when i was first diagnosed as a kid i even avoided the kitchen altogether because i was afraid i would hurt myself or my family  thankfully my mom read up on erp and helped me through it we started just 1 second of touching the knife and then prolonged it until i wasnt so anxious holding it anymore then i had to say the scary words if i touch this knife i will hurt someone aloud and repeat them until i just got tired i cried but i kept with it and now today i can not only hang out in the kitchen for an hour but i can also use a knife to cook or to carve a pumpkin for halloween  sometimes the ocd thoughts about knives still come up every once in a while when im holding one but now im able to bat them away