Answer:
Blade to blade I always win My foe laid low and even. Yard by yard through thick and thin I'm busiest in season.
I am owned by every man though my length differs. Their wives uses me after getting married.
I can run but not walk. Wherever I go, thought follows close behind. What am I?
I go around a yard but do not move. What am I?
The more you have me the less you see. Shine a light on me and I shall flee.
What do you purposefully put lots of in and on your body, but run away from when you encounter it outside?