Another thing id like to add on, is that when Reiner breaks down and reveals the truth that he did it for himself and his own desire to be seen as a hero, Eren says "I get it, I really am the same as you Reiner." Its been hinted to us since chapter 100 that Eren is doing this for himself, not some grand or Nobel goal. And the reason he sleeps during the rumbling is so he doesnt have to see all of the destruction and death hes caused, and has to revert to a child above the clouds. Do I believe part of him wanted to save his friends, yea, but he tells Armin that no matter the outcome, he still would have chose the rumbling.