A mile isn't much, just push through it. I run three every night. :)
Some of the things that I've been told that help though, are: 1. Dedicate every mile that you run, to someone you've lost. 2. "Treat" yourself for running so many miles. So say, after you run 20 miles, you get a new workout shirt. (Or something similar).
There is a app called run keeper it's really good for keeping up with your pace and how many miles you've covered it's free down load it you'll love it. Make sure you keep yourself hydrated and eat energy packed foods like almonds. HAPPY TRAILS