why should we trust literature or not to?

Answer 1

If you are saying should we trust literature or not, it depends on understanding that any text, on whatever level, is open to both reader response and authorial intention-- plus the unreliability of text. The important question is therefore, do you trust your own response to any given literature? Literature is an existential manifestation of the human condition and concerns itself with the nature of identity. Its metaphysical intent--in ontological terms--therefore defines and delineates your response, which will always be unfixed, organic,; endlessly interpretive. Should you trust it? Yes, no, I don't know. What do you think?

Answer 2

I think literature is a world with illusions that created by the writers, but it has a reflection of something, maybe ideas, social problems or something else. And if you believe in what they say and if they give resonance to you, so why not trust them.
So, my answer is: it depends on you.