Buddhist Principle Number 1—Impermanence. Everything decays and eventually dies. Sticking with the old means the old dies of a heart attack, and you’re left alone. Eventually. That’s how it’s always is.
Buddhist Principle Number 2—Suffering. Life is suffering. Good memories inevitably devolve into painful reminders of that which is lost or changed forever. Hope is the first step in the road to disappointment.
Buddhist Principle Number 3—No such thing as the “Self”. Nothing is divided; everything is together. From the moment someone stabbed you in the back, that knife and the injury and evil intent has become perpetually engraved in your body, and your sense of Self. The Individual that is you, is nothing more than the end-result of the lives lived around you and situations outside of your control.
The previous 3 principles is what they call “The Cycle of Suffering” attached to the past, and hurt yourself in trying to preserve what cannot (and perhaps should not) be preserved, intrinsically. The only way to exit this Cycle of Suffering is via:
Buddhist Principle Number 4—Emptiness equals Peace. The only way to avoid suffering, is to empty your mind of attachment and accept that everything you love will eventually decay, and die. And the only way to regain your peace is to let go, and free your mind from desire or attachment. This is what true peace means.
This is going to sound crazy, but…
Giving up is usually the best course of action in the face of adversity. Because adversity engenders MORE and STRONGER adversity as a reaction. It is a never-ending cycle in which long-past glories transform into present sufferings. The best way to win, always, is to not play at all.