"James did learn the truth of what had happened, Peter, just before he and Lily had met their fate," Remus explains. "He was starting to cut ties from Sirius Black, using the fact that he had to hide with Harry and Lily as a good way to start the process. He knew that if he did it so sudden it would spell extra danger, given everything. Voldemort played you like Dumbledore had. You had no way in knowing that, and you were trying to find help for a shitty situation, and you probably had similar thoughts when it came to figuring if you could have trusted me or not, because Dumbledore deliberately coursed a frenzy to cause doubt. Perhaps why Sirius Black got away with his deeds for so long.