When Storm questions the ethics of using the cure, Beast sheds some light on his inability to blend in with other people
Beast: Is it cowardice to want to be free from persecution? Not everyone can blend in so easily; you don't shed on the furniture.
No love for Warren. Does a kid cutting off his own wings because he's afraid of what his dad would think of him not bring a tear in the room?
When Magneto meets with a group of mutants who're declaring their mutations with pride, partially by heavily tattooing themselves, one of them asks him why -if he's so proud of being a mutant- where's his ink? Magneto's response is to simply roll up his sleeve and expose the tattoo he was given in a Nazi concentration camp:
Magneto: I have been marked once, my dear, and let me assure you: no needle will ever touch my skin again.
It just goes to show that- whilst the younger generation of mutants have understandable reasons for wanting to fight back - Magneto will always have them beat. He already lived through one extermination. That's why he will never back down.
When Logan finds Scott's glasses at the lake, he keeps them with him at all times until they're destroyed, possibly as a kind of Tragic Keepsake.
Just five simple words.
"Jean, what happened to Scott?"
Wolverine confessing his love for Jean right before mercy killing her.