Obito was betrayed by
The answer is simple: It's because Obito fulfilled his purpose and was of no use to Madara anymore. By the time that Madara finalizes his plans for peace (Eye of the Moon Plan), he was very old and knew that he wouldn't have the time left to execute it on his own.
Witnessing the death of the one he loved so much turned Obito into a villain who is primarily responsible for the Fourth Great Ninja War. However, Rin's death was merely a trigger, after which Obito snapped and turned evil. Obito's interaction with Madara after being saved by Zetsu is what truly shaped his ideals.
Madara Uchiha was the biggest traitor in the history of the Hidden Village, and that is shown throughout most of the series after the time skip. After being one of the founding members of the village, he went on to manipulate multiple events throughout history to achieve his goals and become as powerful as he could be.
Obito Uchiha was one of the main antagonists in the Naruto series who influenced the plot by a huge deal. Obito was in the Akatsuki and was known as Tobi. Not many people knew his true identity and his mask did a great job in concealing it. Only the Zetsu and Madara Uchiha knew about this shinobi.
Despite his impressive achievements, there is no way Itachi can beat Obito in his most potent form. Obito Uchiha, in his strongest form, was the Ten Tail Jinchuriki. This means he had massive chakra reserves and endurance.
In a short time span, Tobi became an integral member of the Akatsuki and a close partner of Deidara, as the two were sent on several missions for the organization. Even though Tobi's initial childlike persona was due to Guruguru, Obito kept the guise simply to present himself a benign entity to the Akatsuki.
Zabuza was introduced early in the series and was really the first major antagonist in Naruto. This former Anbu of the Hidden Mist Village proved a difficult opponent for Team 7, and he was even strong enough to take on Kakashi. Most fans agree that Haku is the more interesting character of the pair.
4 Obito Uchiha
Surprisingly, he wasn't given the opportunity as he ended up dying at the hands of Kaguya Otsutsuki towards the end of the Ninja War.
Obito in his Tobi persona was Kishimoto's favorite Akatsuki character to draw, because of his simple mask. His nickname (Tobi) comes from Obito calling him Guruguru (グルグル), an onomatopoeia for turning round and round or going around in circles.
Obito Uchiha, also known by his iconic alias, Tobi, as well as the Masked Man, is one of the main antagonists of the Naruto franchise. He is the true leader of Akatsuki and serves as a dark reflection of the titular hero Naruto Uzumaki.
Obito's hate for the Uchiha was simply a result of Madara's animosity towards the clan, as they had betrayed him long ago and had decided to side with the Senju-led government.
Obito grew up to be the real leader of Akatsuki. He started the Fourth Great Ninja War under the name of Madara Uchiha. However, after Naruto successfully used the Talk-no-Jutsu against him, Obito realized his mistakes. Later, he helped Naruto and the rest of Team 7 to beat down Kaguya Otsutsuki.
No, he had zero idea that it was Obito. For one thing, Obito was just one of many names of relatively unknown shinobi on a memorial by the time Itachi was even old enough to read.
Some of Naruto's villains are near-deities, like Kaguya and the other members of the Otsutsuki clan, who are among the strongest characters in Naruto history. On the other end of the spectrum is Zabuza, the series' first proper big bad and weakest villain all.
Kaguya Otsutsuki was an ancient deity who was responsible for the first flow of Chakra reaching human beings. One of the most powerful beings, as all the other Otsutsuki are, she is definitely someone who can beat Madara.
Madara Uchiha
As a brilliant strategist and a bloodthirsty fighter, Madara's influence reaches over many characters in the series, even though he died before the series began.
Under the guise of the brother of Sasuke, Naruto, Kakashi, Sakura and Chiyo face off against Yura, who eventually is killed by Naruto's Giant Rasengan technique. Viewers later see Yura's corpse, confirming his death.
Tobi, also known as Guruguru (Swirly in the English dub), is a minor antagonist from the manga/anime series Naruto. He is one of the many humans that fell victim to Kaguya Ōtsutsuki's Infinite Tsukuyomi in the past and was transformed into a White Zetsu.
Tobi is a gender-neutral name of Hebrew origin. This name translates to “God is good” and is a diminutive of the name Tobias. Tobi itself offers a contemporary slant to a traditional Biblical name, with its 'i' ending landing it directly in our modern age.
However, in Naruto: Shippuden, Tobi reveals his true identity as a 31-year-old Obito Uchiha. He was 5'1" in the Kakashi Gaiden, with his height varying between transformations in Shippuden.