"It reminded him of how he had needed
A place to go in his own direction,"
Um...
I think that in these lines Wallace Stevens is explaining that to him, poetry allows him to collect his thoughts and reflect on life. Just as in the title, "A poem that took the place of a mountain." Many people go to a place such as a mountain that is peaceful, this gives them a chance to gather their thoughts and think. It is a way of relaxing. Wallace uses poetry to relax and calm his nerves, it takes him away from reality and the pressures of the world. This gives him the chance to get himself back together and focus on where he needs to go in life.
But then again, I'm probably wrong.