What exactly happened in 1991 (SPOILERS)
Samuel Jackson was hired to kill Mr. Hayes. Unbeknownst to him, it was Hayes himself who organised it, with the intent of faking his own death.
The part that I didn’t understand is the killing of Anna’s family. Who were those guys? A gang that Samuel Jackson hired as part of the plan to kill Mr. Hayes? And how was Anna’s family involved? Were they just innocent bystanders? Obviously there was some connection between Samuel Jackson and the gang, as he went to the place where they were hiding, only to find them all dead.
If Samuel Jackson hired the gang, then he is indirectly responsible for what happened to Anna’s family, which changes everything. She probably never suspected it, but he would have known and carried the guilt the entire time.