You don't need to be high on it.
If you think about it, life is all you know. All your memories, events, possibilities, knowledge is based on life. When you die, it'll all disappear. What do you have left? Nothing, you don't even exist. I tell you, I'd rather fight till the end to survive rather than such a fate, it's horrible.
Even if you've been through shnit and you ain't exactly having the time of your life you must still now that it's within your reach. If you give up, you'll have nothing, nothing at all, not even yourself. Not a chance to get better, get well, everything will just be empty.
I would even live a life as a poor guy on the street that everyone spits on and hate as long as I live.