I get that same unfortunate impulse. Fortunately, I don't carry a knife (and have been able to resist at home, but I know how strong those impulses can be -- it's an awful feeling). Maybe not carryning a knife? In the spirit of keeping things we tend to have problems with out of our vicinity? Btw, I don't think you're weak. (The only thing that's kept me from it is a greater fear of serious injury and scarring to live with forever.)