That’s probably what stood out the most. Peter had every reason to become bitter after everything he’d lost, yet the first thing Jean finds in his mind isn’t anger or hatred, it’s compassion. That’s what separates him from a lot of heroes. His circumstances changed, but who he is at his core never did.
I feel like people are forgetting they were friends before they were lovers and Peter isn’t a loser who acts out because he got rejected. What MJ said was entirely reasonable and Peter understands that.