house indoril was very xenofobic and hated the empire but in the mainquest youre sent by the empire and you become nerevar to defeat another xenofobic house it doesnt make much sense to me can anyone explain me that part?
Some of the Houses are more xenophobic than others. House Hlaalu is the most "Imperialized" one, led by King Helseth who has made an alliance with the Dres. As the PGE 3rd mentions a couple of years before the Oblivion Crisis: "The Great Houses themselves, long stagnant, are adjusting to the new powers in the land. Some, like Dres and Hlaalu, appear to be on the rise, embracing the new traditions while welcoming the return of the old. Others, like Indoril and Redoran, seem to be waning, unable to change with the times. "
Dagoth Ur wanted to destroy the Imperials and all Dunmer who wouldn't convert to his cult/House. In a way, you're defending the Empire as well as the Imperialized Dunmer by destroying the Sixth House; and even though the Ashlanders are also xenophobic, you're saving them as well by destroying Ur (whom the Ashlanders consider the devil). Along the way, you're also a pawn of Azura in helping destroy the last vestiges of the Tribunal, but it can't be helped (and Vivec understands this).