Well duh, from part1-chunnin exams, they were friendly rivals
if you have read whole manga from 1 to this point you would understand that.
They have a brotherly relationship. The constant fighting isn't that odd. Btw, Sasuke failed to capture Bee. That tentacle was fake; if that's what you're referring to, that is.
That tentacle was still enough to revive the Juubi, remember?
People act like sasuke knew.obito was going to try to enslave humanity in IT. You might as well write a fanfic saying sasuke.was in on the plan all along with Kisame, ztsu and maddara. Yes naruto sees sasuke as a best friend. Its a retarded forced relationship on narutos and kishis part. Thank god sasuke just ignores his idiotic comments and doesnt acknowledge narutos bs anymore.
It was a plan of a terrorist organization which all the members at least knew they were going to make a country destroying weapon(the Juubi). Obito said that he had the same goal as Sasuke. Which was to destroy the leaf. Sasuke knew he was up to to no good.
Obito lied obviously. His plan was never to destroy the leaf and Obito was just using the akatuski. The end goal was to see Rin in a dream world. Sasuke knew nothing about this and the fanfic isn't helping your argument. Sasuke wanted to destroy the leaf that was no secret but that had nothing to do with the Juubis revival.