Do not desire anything. Do not try to avoid the inevitable and the fated. Only things under your control can be called good or evil. Be your own master. Depend on nothing outside of yourself.
Nature gives and nature takes away.
External goods do not last. Depend only on your reason, which is a spark of divine reason. Do not depend upon other people. Do not become so attached to other people that you cannot be happy without them. Know that even your spouse and children are human beings, are mortal.