One More Light. Cry for help or the last goodbye?

Already thought after listening to "One more light" and "Nobody can save me" that it is like a last call for help or like he's saying goodbye to everyone. But the whole album is like that. "Heavy" It makes me so sad, that nobody was there, to save him. I recherched and wikipedia says that Chester only wrote one of the songs. But it just matches to good, to be coincidence.