Public Searches For Reason
Most of the rumors claimed Brad Pitt was an alcohol addict and a heavy drinker. Some sources even said he faced drug abuse. People speculated that Pitt and Jolie faced problems and filed for divorce. These could be the reasons.

Public Searches For Reason
A Suspected Affair
An affair could be another possible reason. Some speculations claimed Brad Pitt had an affair with a famous person he was working in his film Allied, Marion Cotillard. These fraudulent rumors finally were denied, leading people to think of other options as to why Jolie-Pitt filed for divorce suddenly.

A Suspected Affair