Truths of the observer require you simply to observe things and try to figure them out. Truths of the will, which cover relationships are skills, are things you have to bring into being or they never become a reality. In this area faith, confidence, and conviction make all the difference.
Coming to terms with the inevitability of your own death and the death of those you love. If you wait until the time of death in order to think about these things, it's a huge shock. This is one of the reasons the Buddha has you contemplate if before death.