<p>I will give you my point of view for each person
</p><p>1-Obito was exactly the reflection of Naruto,he was the stereotypical "loser" that everyone could make fun of him,even if he was full of oneself and always talking big,he was in the inside feeling down because he couldn't be just like Kakashi;he was carrying the "burden" of being born in the strongest clan in the Leaf and he couldn't meet his fellow clan's expectations,he was just like Madara stated "too much kind" to the eledery,to his friends,to his village;he was deeply in love with a girl who was never romantically interested in him,and he was suffering every day watching her romantically attracted to his rival,he had enough suffering every day,and unlike we think all;his "curse of hatred" started when Kakashi prioritized the mission of the destruction of the Kannabi Bridge over saving Rin,he clearly stated that "And if breaking the rules makes me the wrong shinobi then I will crush all the so-called shinobi" (chapter 241),he nearly died once protecting his friends and giving his Sharingan to Kakashi,only to be saved and witness the death of Rin,after that,he lost everything,"he was in hell" and was filled with hatred against that world,that shinobi system of village "patriotism" that make Rin sacrifice her life and was resolved to build a new world,when illusions can fill his empty heart as he stated,only to be saved by Naruto who show him again the right path,that peace can also be available by cooperation between villages,before sacrificing his life to protect it again
</p><p>2-For Sasuke,he was constanly worried about how his beloved brother was shading him in front of his parents and the Uchiha clan;and one night,he find out that his beloved brother coldly killed everyone he cared about,and he become alone,and after meeting and forming a "golden" bonds with the team 7,his brother appearance make him realise him that he is weak,worthless and that he could never realise his revenge,that's why he decided to "cut" his bonds,believing that will make him stronger if he's alone,and after FINALLY "avenging" his clan by defeating Itachi,he found out that EVERYTHING was a lie,that his elder brother has always cared for him,and that he was driven by duty to kill his own family,so he sought revenge against Konoha who took everything from him (his family,his elder brother,his happy childhood)
</p><p>3-For Indra,he was manipulated all along by Black Zetsu,and according to anime fillers,he was always caring for his little brother,he even awakened his Sharingan while he was protecting him from the boar,even the Rikudo Sennin admitted that it's partially his fault for not watching over him and teaching him effectively the principles of Ninshu,he sought peace,but peace when everyone should be submitted to power
</p><p>4-For Madara,he was born in the era when children where soldiers and they probabely never make it to adultehood,he already lost four brothers killed by the Senju clan;and he was always sharing Hashirama's dream of perpetual peace,but when Izuna was killed,he lost everything he was fighting for,he changed and started to hate everything,and even after co-creating the Hidden Leaf,he was quick to realise that he can't protect the Uchiha clan as he promised to his brother,and he just seeked to realize peace in different manner,in a world of illusions when everyone will be happy,even "against their will"
</p><p>For the Uchiha clan members,as long they know love,there is a risk to know pain and sufferring,and when they do that,they bear heatred to anything,and as long their heatred grow,they acquire immense power.
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