When you know how and when to kill yourself then only the untrue self dies, and by the self I do not mean your body.
The REAL YOU and all else will live as life will be, and only the perceptions of your self will die.
Hence when you know how to kill your self, you know the TRUTH of life because you know what you ARE and, at any moment, what you need to be.
Any other truth is only an illusion (a lie) because you are what you ARE and when you really KNOW that, that is when YOUR cries and laughter become ONE.
See an extract from The Dark Knight movie below as an audio and visual pointer to the words above and the following words may give you an overview of the extracted scene.
The scene below shows Batman taking it upon his self to take the responsibility of murders which were in fact done by a perceived "white knight", but where Batman realised that if the general people, who somewhat looked up at the white knight as their saviour, in fact, discovered that he became a murderer through revenge, all perceptions of saviour would have been extinguished in the people.
Hence Batman had to kill his self to maintain hope (of saviour, and life).
If you have not seen the movie then please watch it, all. I also recommend the previous movie, Batman Begins.
Appreciation:
Warner Bros : The Dark Knight movie.