I think it's because of partly guilt and also the indoctrination of pro-life values when they were young, by their parents, media, school, authority figures, etc., then when their worldview (A just world, a beautiful life, how life is superior to death, suicide is a result of mental illness, etc.) is shattered, it sends their mindset into chaos so their response is anger and criticism. I'd like to think the quote "You can't handle the truth!" said by Jessup really applies here, even if that is a stretch. It appears that most people (mass populace of NPCs (Non-Player Characters, or Normies some may wish to call them) like to be told what they 'want to hear' rather than what is 'the truth'. If you tell them 'the truth' (aka life sucks, life is meaningless, life is full of suffering, life is not fair, etc.) they lose it because it shatters their fantasy, delusional worldview of how great life is.
Some could claim that religion and the concept of a 'God' is conceived because there is no meaning to life and the aversion towards death, so humankind/mankind decided to invent the concepts and put them to practice as an 'response to death. Most religions are very anti-death and emphasize the afterlife as a cope towards the meaninglessness of life and existence, but I digress.