It would be an injustice not to say that Peter Parker was an emotional person. This all came as a total shock to him. He listened pretty patiently until MJ got to 'and then Steve was killed" and "you got Aunt May with a bullet in the chest". It was worse than anything Peter would have come up with on his own.
By the end, Peter was standing there with a hand in front of his mouth. He thought he might throw up and it was clear he was on the verge of tears. Steve dead, Aunt May dying, making a deal with Mephisto.
Eventually, he had to hold a hand up to stop her. "All right, all right, all right. I need... you know, I'm gonna sit down."