Even during his week long camping trip he was emotionally losing it.
I think we might be a bit harsh regarding Mr. Wardle's performance. While it is true that he has made mistakes, most of which have been thoroughly discussed here, and that some of the expert survivalist may grade his performance as average, I daresay that I would be most pleased with myself if I spent 50 days in the Yukon and still had a week's food supply, a credible shelter, and some equipment left over with which to persevere. What I can't imagine, and am holding the mirror up to myself and the rest of us for introspection, is the degree to which we could stand suffering both the isolation AND fear for that long a period.
Individually, isolation and fear can have devastating effects on a person's psyche. Ask the multitude of psychotherapists who deal with the aftermath of clients and patients who have failed to negotiate with their fears, or whose repression of memories of isolation manifests itself in a variety of unhealthy ways. Talk with prisoners who have spent extended times in isolation, even though their meals and shelter were provided. Talk with people who suffer from debilitating fears such as claustraphobia.
If one or the other can produce such drastic effects, then imagine them both. Together, they can produce terror of which Hitchcock would be envious. Despite the flyovers and minimal human contact, living 20 to 22 hours of each day in an environment that makes you afraid has to be a tremendous mental challenge. It's no wonder that he was "mentally losing it", then or now. The week prepared him a little; this experience probably prepared him a great deal. I strongly suspect that prior experience, or perhaps specific, arduous training, is the only way one could survive under those conditions.