Meaning of the word "what the eye does not see, the heart doesn't grieve over" in English

What does "what the eye does not see, the heart doesn't grieve over" mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

what the eye does not see, the heart doesn't grieve over

US /wʌt ðə aɪ dʌz nɑːt siː, ðə hɑːrt ˈdʌz.ənt ɡriːv ˈoʊ.vɚ/
UK /wɒt ðə aɪ dʌz nɒt siː, ðə hɑːt ˈdʌz.ənt ɡriːv ˈəʊ.və/
"what the eye does not see, the heart doesn't grieve over" picture

Idiom

if a person does not know about something, it cannot make them unhappy or cause them pain

Example:
I decided not to tell her about the minor scratch on her car; what the eye does not see, the heart doesn't grieve over.
He keeps his secrets from his wife, believing that what the eye does not see, the heart doesn't grieve over.