Quote from : X-Men: Days of Future Past Movie

Charles Xavier: When did you last see her?
Erik Lehnsherr: The day I left for Dallas.
Charles Xavier: How was she?
Erik Lehnsherr: Strong. Driven. Loyal.
Charles Xavier: How... how was she?
Erik Lehnsherr: She was... We were... I could see why she meant so much to you. You should be proud of her, Charles. She's out there, fighting for our cause.
Charles Xavier: Your cause. The girl I raised, she was not capable of killing.
Erik Lehnsherr: You didn't raise her. You grew up with her. She couldn't stay a little girl forever, that's why she left.
Charles Xavier: She left because you got inside her head.
Erik Lehnsherr: That's not my power.