Buy her a dozen roses and tell her you wanted to make her feel better because you could see how badly she felt. Then, when she's hugging you, tell her you're just glad you decided (at the last minute) to strop the blade, otherwise it would be your face cut up and not your strop. Milk it for all it's worth.
Evil, pure evil .. although ...??
I could always try claiming that the strop was given to me by my father on his death bed, handed down to him by his father and so on. Although she is probably aware that my father is still alive. And I have this sneaky feeling that she may have bought it for me in the first place. Unfortunatly the personal injury angle is out, she is an A+E nurse in an increasingly jaded health-care system and unless I am literally dying on the floor, there is a good chance she will tell me to stop being so lazy and to clean up the blood before it stains the carpet.

Thanks JimmyHAD, I will give the back-honing a try.