Bad run > no run. I have to remember this, getting up and doing SOMETHING is better than doing nothing! That's why I ran this morning even though it was the last thing I wanted to do, and I felt AMAZING afterwards!
I dont run because I love the the feeling of running. I run because it makes me love the feeling of living. While I do love the feeling of running, I also love how it helps me love the feeling of living.
I'm by no means a runner - I have avoided it like the plague in most cases. But occasionally I feel like running just because I can. There will come a day when this body just can't do the things it used to. Live life while you are able to.