Obito: Manipulated by Madara, nice kid beforehand.
Madara: Felt pressured by Tobirama and essentially anybody that wasn't Hashirama into leaving the village, jury still out on how he really is (We know he's a dikk know, but you know what I mean).
Itachi: Decent guy actually, manipulated by Danzo, Obito, insurrectionist elements of the Uchiha and absurd archaisms of the village into killing whole clan. Crushed about it afterward, wanted to repent.
Insurrectionist elements of Uchiha: Well, shyt, if I were a part of a clan that made a truce of peace and equality with a clan we used to hate, then our former leader said that our formerly hated rivals would take power within the village and subjugate us, followed by the bigoted little brother of our formerly hated rivals taking power, excluding us from all affairs of the village and exiling us to a tiny part of our own territory with nothing but a meaningless, symbolic organization to our name, thus proving our former leader completely right, then yeah, I'd want to band together and take our power and territory back as well.
Sasuke: Manipulated by everyone he knows not named Naruto, is a complete mess as a result.
Saying that they're inherently crazy is absurd. All I see is the result of idiotic and discriminatory practices toward the Uchiha by Tobirama and his ilk. Hell, even if Hashirama had gotten what he wanted and given Madara the position of Hokage, and then Madara flipped out, none of this discriminatory stupidity probably would've happened, because then it would've been just on Madara instead of the Senju proving Madara right.
And honestly, if we replaced "Uchiha" and "Senju" with "Black" and "White," everyone would be pulling for the Uchiha right now. Coli hypocrisy at work now.