"As if you'd let me talk you out of anything," Eren says. He knows better. If he argued against it, Jean would probably dig his heels in. Eren would have when he was younger. He might now, depending on the circumstances, but he's no longer inclined to just pick a fight with Jean about nothing.

He grew out of that and decided to pick a fight with the whole world instead.

"I know you don't want to die again. But if you're going it alone, we can't help keep you safe. You're a capable person. But…the captain and Hange told me to tell them if stuff is wrong. That goes for you too. Even if you don't wanna tell me."

It's sort of his way of agreeing that he won't hide everything.