If we don't take the life of other beings, wouldn't we starve, thus taking our own lives?
But aside the idea of "we", Nyom Valjean. There are many who either live from taken what is given, left over or harmess trade, either kill by themselves, give signs so that other kill and do not aprove taking life mentally.
Abstaining from taking life, the gift a letting others live, is actually not only the reason to gain heavenly existences but if gaining a human life the cause of "naturally" long live.
So the idea that "i die when I don't kill" is actually a very animal like thinking, an existence where there is not much space to make any merits.
And one, especially in "developed" countries living, has no need at all to kill.
And one should not forget that most killing conducted by humans is not really to simply maintain the body but out of desire for sensual pleasure and desire for gains.
Out of knowing that no being has someone more dear as oneself, respecting that, one abstains from killing and in that way, by making a great voluntary gift on has gifted one self to long term happiness.
As beings are not used to virtue, don't know the fruits, it takes of course much confidence, faith, to act good in advanced, before one gets known it's truth by oneself.
It's a matter of gratitude, right view, of cause and if not seeing, starting from ones own mother, that there are many who could, but do not, take yours, than one is wrapped in wrong view, acts for his own and others pain:
"And how is one made impure in three ways by mental action? There is the case where a certain person is covetous. He covets the belongings of others, thinking, 'O, that what belongs to others would be mine!' He bears ill will, corrupt in the resolves of his heart: 'May these beings be killed or cut apart or crushed or destroyed, or may they not exist at all!' He has wrong view, is warped in the way he sees things: 'There is nothing given, nothing offered, nothing sacrificed. There is no fruit or result of good or bad actions. There is no this world, no next world, no mother, no father, no spontaneously reborn beings; no brahmans or contemplatives who, faring rightly & practicing rightly, proclaim this world & the next after having directly known & realized it for themselves.' This is how one is made impure in three ways by mental action.
So one with right view,
trains his thoughts like this:
"And how is one made pure in three ways by mental action? There is the case where a certain person is not covetous. He does not covet the belongings of others, thinking, 'O, that what belongs to others would be mine!' He bears no ill will and is not corrupt in the resolves of his heart. [He thinks,] 'May these beings be free from animosity, free from oppression, free from trouble, and may they look after themselves with ease!' He has right view and is not warped in the way he sees things: 'There is what is given, what is offered, what is sacrificed. There are fruits & results of good & bad actions. There is this world & the next world. There is mother & father. There are spontaneously reborn beings; there are brahmans & contemplatives who, faring rightly & practicing rightly, proclaim this world & the next after having directly known & realized it for themselves.' This is how one is made pure in three ways by mental action.
Godd ways start with right view, with gratitude. And if bringing the fact in front of who much has been given by others, only in this life, then there is much reason to syart to beginn to give something back, and one is not asked to sacrifices once own life at all.
Explore it, test it, try it, no need to blindky believe, Nyom Valjean, that freedom of any fear is possible by ones wise deeds. Happiness that causes others pain would not last long. You would be haunted all the time, and others would not like to see you being happy at all.
