I'm guessing this would happen to a Jedi during their training, seeing as how they would have to learn to overcome their weaknesses and fears alone, eventually. They would also learn how to cooperate with others and to work together to solve the tests and trials. E.g. Juhani and her near fall to the dark side after she attacked Quattra, Luke and his journey through the Dark Side cave in Dagobah without Yoda, Jolee leaving the Jedi before he attained Knighthood due to him secretly training his wife to be a Jedi (while he was still a Padawan) against the Council's wishes, etc.
You could also point out Jolee and Juhani joining the quest for the Star Forge as a cooperation test. Juhani either volunteered to join and was accepted, or was recommended by the Council to join. As for Jolee...he joined Revan and the others in his own accord, instead of staying in Kashyykk or being
tossed out dropped off by Revan somewhere desolate, like Hoth.

Jolee's still great, though.
