What did they do to torture Peeta Mellark?

Peeta Mellark was subjected to psychological torture by the Capitol, particularly during his time in the arena and after his capture. He was forced to undergo hijacking, a process that involved manipulating his memories and emotions through the use of tracker jacker venom, which left him confused and traumatized. This resulted in him being led to believe that Katniss Everdeen, whom he loved, was a threat, causing immense emotional pain and suffering.