Jedi Order as a whole
By the time Anakin showed up at the Jedi Temple at age ten, the organization he had spent so much time idolizing was already on the brink of collapse given its interference with politics when they were supposed to be apolitical. However, this continued to spiral over the next thirteen years and Skywalker couldn’t help but notice its decline.
By the time final year of the war rolled around, Anakin’s frustrations were at breaking point. While he had his reasons for hating what the institution he had dreamed of joining as a child had become, it was Palpatine machinations that pushed him too far.
When Ahsoka, Anakin’s Padawan was framed for murder by her friend Barriss Offee, he did everything in his power to clear her name. However, he had endure her being expelled by the Jedi Order so that she could tried in the Republic Court System. With nowhere left to turn, he asked Padmé to represent their young friend while he hunted down who was actually responsible.
Evil Palpatine served as the judge during the trial and was ready to deliver the verdict when Anakin rushed in with the actual culprit who didn’t deny her guilt. Anakin’s frustrations with the Order had been brewing for a while, but the way Ahsoka was simply discarded because the ‘evidence’ pointed at her was just one of the few factors that broke his spirit and his faith in them.
Jumping back a couple of years, and Anakin knew marrying Padmé would destroy their careers. But they went and did so anyway, despite it being against the rules of the Jedi. He mentions it several times and it comes up when they reunite after the rescue mission to save the Chancellor from Grievous and Dooku. It’s here that he tells her he no longer cares if the Jedi Order knows of their marriage.