People who get sad looking at other people's lives on Instagram are likely so emotionally fragile that they'd probably get sad reading a book about other people's lives. Burn all books. "I burned my books, magazines, and eReaders and I FEEL FUCKING AMAZING OH MY GOD IF YOU COULD EXPERIENCE THIS LEVEL OF PURE UNADULTERATED JOY AND CONTENTMENT YOU WOULD SHIT YOURSELF."
False equivalence. Images and written text have different effects on the brain and emotions. You follow famous people on social media, who have 1,000x your wealth, travel all the time, get adequate sleep, meals, and exercise -- and it can chip away at your self-worth in a way books just can't.
Sorry, editing to clarify because this sounds unnecessarily combative. What I mean is your self-worth should not be externally determined by where you stand in some (mostly imaginary) ranking system compared to random strangers or celebrities, thus it should not be chipped away at by seeing anyone doing better than you in some aspect. This is a crucial skill to learn. You don't have to let your mood and self-worth to be subject to random vagaries of whatever you happen to be looking at at the moment.