He isn't getting his revenge if he wants to keep his promise to Naruto anyway to kill him first so this is all pointless. He feels that Konoha's peace comes at the price of his brother and clan and hates them, which is understandable but there are more people than that he should hate.
After Itachi came he became calmer and started think more deeply and realised he will need help that is why he accepted it from Oro.