Now we have done it. Opened up an invitation to me to list some "addiction" mountaineering quotes. Harvey

This one starts us off gently
"We succumbed to the occupational disease of all mountaineers. After initially absorbing the beauty of the scene, we automatically began to select routes up the surrounding peaks."
Nicholas Clinch, A Walk in the Sky, page 193

This one is stronger, hammered out in the cruel world of winter Himalayan climbing:
"Now I had come to know that I would not stop climbing; this mountain scene was exhilarating rather than oppressive, full of endless opportunity. Sometimes I feel as if the mountains have become an addiction, the pleasure gone, the compulsion to partake remaining."
Joe Tasker, Everest the Cruel Way, page 118

This dark and final one, no pun intended, is why some people prefer living their lives out there:
"But no journalist wrote about the banality of city life or how easy it is to become another automaton paying bills and working nine to five and being so removed from the primary necessities of life and so far from real fear and natural beauty and human instinct that when death finally approaches in some antiseptic white room, just as you have been waiting for it, you sense that you have already been dead for years."
Jonathan Waterman, In The Shadow of Denali, page 246