The way to get through ...

The way to get through anything mentally painful is to take it a little at a time. The mind can't handle dealing with a massive iceberg of pain in front of it, but it can deal with short nuggets that will come to an end. So instead of thinking, Ugh, I've got twenty-four miles to go, focus on making it to the next telephone pole in the distance. Whether you're running twenty or one hundred and twenty miles at a time, the distance has to be tackled mentally and physically one mile at a time. The ability to compartmentalize pain into these small bite sizes is key.
 Joe De Sena

Quotes from the same author

You can either go to bed satisfied with your efforts today or stressed with what you left for tomorrow. You can either work hard to take on the hill or never know what it is that people see at the top.
 Joe De Sena