As well as harden the heck up, I've got some other good advice. I'm hoping you all have some sort of goal in mind.
Your goal need not solely be a time goal, it could be as simple as running the entire 21km without stopping. And if this is your first half marathon, that's a worthy goal. A goal gives you more focus, and if well set, it gives you a greater sense of achievement. And here's the best bit: it gives you a reason to return the following year and have another go!
Here is how you achieve a goal. First, work out if it's realistic - challenging, but realistic; and then you go after it. But go after it the right way.
Scoring a century in cricket was often a goal for me but I didn't go out to score that century. I went out to follow the process required to end up with a century.
My process wasn't to get to 10 and then get to 20 and then 30 and so on, it was more like get through the first over ... see off the nasty fast bowler. Bat for 10 overs, get through to lunch, start again, dominate the bowler having a bad day, get to the second new ball, see off the second new ball ... and hey presto I've made 100.
Work on your run like that; run hard in places - survive the hill, recover a bit on the downhill. Think about your running technique when you're hurting ... see how many road markings you can count ... achieve on the way and you will achieve the end.
Good luck! See you all at the Hamilton Half Marathon on October 6.
Enter at hamiltonhalfmarathon.org.nz.