In the one-true-talisman department, I can't think of a better universal solvent than ... the most important thing in life is to be kind.
It is not, as many infer, the most important in some smarmy or religious sense, a sense oozing with virtue. Basically it is most important because it is self-serving ... best for you. It is only tangentially most-important because it's nice to make nice and the social wheels are greased. Altruism is good as far as it goes, but it can never go quite far enough.
What goes the distance is kindness.
The more you praise it, the less competent it becomes.
Just be kind.