Obsessing over anything, and getting nervous or anxious, is almost never good, no question. That said, everyone takes at least some things seriously in life. Even your friend who advocates a relaxed and calm life certainly has at least a few areas in her life where she makes sure not to slip up, because those are the areas that really matter to her.
I think it’s important for everyone to realize that chinuch is among the most important things in life, and putting thought, effort, and energy into properly nurturing the neshamos Hashem entrusted us with is something we should all do. Taking the job seriously is very important indeed.
The Gemara, based on a passuk in Tehillim, describes two kinds of darkness and the effects they have. This world is compared to darkness, because we are often misled by the influences around us that cloud our vision. One type of darkness is so dense that it renders us blind — we can’t see where we’re going at all. The other type of darkness, a dim and inadequate light, is more dangerous: We think we can see, but we don’t realize that the darkness is confusing us into believing that, for example, a pillar is a person or a person is a pillar.
In this physical world, we are often blinded and trip over obstacles, not realizing what’s going on. That should teach us to be careful of where we step, and to look for guidance along the way. However, a person who doesn’t realize that his eyes are deceiving him in the dim light doesn’t bother to ask for guidance because he has misplaced confidence in his own abilities, and so he stumbles forward, slipping up all over the place, without realizing that he should be very, very afraid of all the pitfalls before him. He mistakes good for evil and evil for good, and each time he takes the wrong path, he becomes more and more convinced that it was, really, the right path, only the signpost was wrong, or the last person he asked for directions made a mistake... At the very gates to Gehinnom such a person will still be convinced that he’s about to enter Gan Eden and that anyone who tells him otherwise is not to be trusted.
