Steve's pretty sure the reality of the situation is the suppressants giving out, given the way that headache is escalating and what he can feel the rest of his body trying to do. Especially given that he's eating but he's absolutely not interested. And he likes both food and this.

He isn't sure he's going to explain that to Bucky.
He isn't sure he isn't going to.

He is damn grateful any scent involved on his end is blocked.

"Because it's not safe for anyone else, and it's especially not fair to you." Not after seventy years, everything done to Bucky and, hell, their actual history and Steve's refusals before the serum.