I suggest you not try to over-analyze your situation. The whole idea behind cycle touring is to have fun while you're sightseeing, exploring, and reveling in just how far you are able to go on your own power. If you're not having fun, are sick, or injured, it's better to abort then to suffer along in misery or take the real chance of further injury. I've done quite a few tours of over 1000 miles, most solo, and have aborted a couple a bit short of my goals because things weren't going well or I was badly injured....didn't stop my enthusiasm for wanting to go on another tour, just allowed me to prepare for the next trip more thoroughly. Traveling with someone will help give each a moral boost to get over depression spells if things aren't ideal, but you have to be careful about continuing with an injury because you don't want to disappoint your buddy. On a long tour down the west coast, a buddy did just that, not complaining about injured knees and heel tendons until he could barely walk....he was laid up for weeks after getting home.